UB: huge Pratchett fan here, too. Didn't know he was a "sir", though. 
 
Thanks to your suggestion, I went on Amazon to verify that I'd indeed read all things Pratchett and was delighted to discover a couple that I hadn't. I think I might traipse on down to Half Price Books today and buy all the DiscWorld they have, and present them as a gift to my nephew. He'd probably like Le Guin, too, so even though I've read them all I might grab a couple of those as well.
 
Thanks to everyone for the suggestions. More than I can possibly take on one trip (or afford to), but I'll bookmark this thread for future reference.

Magic Russ

ston
Any of the Culture series by Iain M Banks

Not every one in that series.  I wouldn't have minded if I skipped Matter, and The Hydrogen Sonata gives away the ending way too early in the book.

I like "Matter", but "The Hydrogen Sonata" is one I'm less enthusiastic about, just find it hard to get into for some reason. For anyone wanting to dip into Banks' Culture books the first of the series, "Consider Phlebas" is probably the best place to start, then as you say the next book places a lot of that one in context and is probably the better of the two. Though I'm not sure how much sense a lot of it would make without reading Phlebas first.

Banks' early death was a great loss both to sci-fi and "mainstream" literature.

Bernard Cornwell's Uhtred of Babbenburg series already having been mentioned, his other works set in the pre-modern age are also pretty good. The Arthurian series is an interesting take on the legend of Arthur, complete with a Merlin whose magic tends to leave you (and the characters) thinking "did magic really cause that, or was it just a coincidence?" A good way to handle magic without letting it take over or provide instant get-outs when the author writes him/herself into a corner.

Cornwell's stand-alone novel "Stonehenge" is also very good indeed.

tlw
...
Bernard Cornwell's Uhtred of Babbenburg series already having been mentioned, his other works set in the pre-modern age are also pretty good. The Arthurian series is an interesting take on the legend of Arthur, complete with a Merlin whose magic tends to leave you (and the characters) thinking "did magic really cause that, or was it just a coincidence?"
...

Even better ... if you can, catch all 16 episodes of "Sharpe" in the series with Sean Bean. It is excellent all the way though and if anything, although not exactly historically perfect, there are many details in there, like the whole confusion in Spain with the French and the English, and its spies and mercenaries. The whole thing is well written, but in some ways, I like the shows better and now have all 16 episodes.
 
In the start, there is a Spanish actress (Assumpta Serna), and if you really want to watch a most special film on fencing (like differences between French, Italian and Spanish styles and they making fun of the English!), catch "The Fencing Master" ... directed by Pedro Olea and it is an amazing film that will surprise you in the end! She is also in Pedro Almodovar's film "Matador" with Antonio Banderas I think. She is now an acting teacher I understand. 

The Sharpe books are way better than the TV series.

In my opinion of course. The same goes for the BBC's attempt so far to serialise the Uhtred books.

While we're on the subject of books, let me put in a plug for a novel (non-SF) that should interest a great many regulars here - I have to believe that it's a story that would appeal to almost any musician. 
 
The book is Body and Soul by Frank Conroy (not to be confused with Pat Conroy who has cranked out a fair number of "beach reads").  Frank Conroy taught writing and authored a very critically acclaimed memoir.  Body and Soul is his only novel.  It's a coming-of-age and coming-of-artistry story of a brilliant young pianist. 
 
Inexpensive used hardback copies should not be hard to find on-line.  Highest possible recommendation.
 
As a side story, Frank Conroy was reportedly a pretty fair jazz pianist.  He was visiting a publisher having something to do with music one day.  While waiting for his appointment, he sat down at a piano and started to play some jazz.  A bass player and drummer came along, liked what they heard, and just sat in and jammed for a while.  It turned out that those two musicians happened to be Bill Wyman and Charlie Watts.

Hi,
More stuff, way out there!
 
Doris Lessing - Briefing for a Descent Into Hell -- Outstanding fast read and she is super. I even like to recommend "The Golden Notebook" to men, who think they are men, instead of people!
 
Carlos Castaneda - The Art of Dreaming -- Probably his best book, and it is an in depth look at dreams, although it might romanticize them some, it still is one of the best books on the subject ever written.
 
Aleister Crowley - Diary of a Drugfiend -- Not for everyone, but the trips in there are something else, and the resolution ... is absolutely tops and the best anti-drugs book ever written. In a way it debunks the stoned mentality for doing serious inner work. Nope, you have to get it straight from the source, not with anything else. Very serious read, but intense.
 
Aldous Huxley - The Doors of Perception -- At our age, a lot in this book still shines ... and shines ... and shines!
 
Herman Hesse - Steppenwolf -- It was a few years back a bit of an idealistic thing about something else, but when you read it now, it is something else. It is somewhat idealistic about the INNER trip, but it is very good. Also nice reading is "Siddartha", though I kinda think it is a bit preachy now. Steppenwolf is not. (AND, IF YOU CAN FIND IT, a guy named Fred Haynes did a movie version of this with Max Van Sydow, and various cartoons doing the philosophical parts, and it was great ... but way too out there!)
 
Aguirre, the Wrath of God - The film with Klaus Kinsky by Werner Herzog. Watch carefully to see how well it was coreographed to the music, specially the last 20 minutes. And the opening ... is a visual delight. The acting? Free form ad lib all the way through, just about!
 
Aria - A film with bits and pieces of opera arias done by various well known film directors, and you gotta love Jean Luc Godard's ... finger to the whole thing!
 
Magic Trip - About Ken Kesey and his Further trip. Make note of his editorial comments towards the end. The whole thing explains the "beat poets" so well ... and still makes me wonder why music can't do this!
 
Not Mozart - English crazyness and a whole bunch of folks doing Mozart in a way that you have never seen. The whole thing is insane inside out, but fun to watch. Peter Greenaway's opening thing is the best Bob Fosse you will ever see.
 
Prospero's Books - Peter Greenaway's take on The Tempest. If you ever want to really know what words mean, just listen with eyes closed to Sir Gielgud read this stuff and play the main character. It is simply insane, and the words are so crystal clear ... you never thought of Willy as that good, but it changes how you read him next time.
 
Have fun ... I'm done suggesting stuff out of left field ... anything else is too conventional. Or you can just enjoy another Harry Potter kitchen secrets book! I didn't even get to Italians, or Polish films (gotta see the double life of Veronique ... you gotta ... fantabulous music by Preissner)

Moshkito
Hi,
More stuff, way out there!
 
Doris Lessing - Briefing for a Descent Into Hell -- Outstanding fast read and she is super. I even like to recommend "The Golden Notebook" to men, who think they are men, instead of people!
 
Carlos Castaneda - The Art of Dreaming -- Probably his best book, and it is an in depth look at dreams, although it might romanticize them some, it still is one of the best books on the subject ever written.
 
Aleister Crowley - Diary of a Drugfiend -- Not for everyone, but the trips in there are something else, and the resolution ... is absolutely tops and the best anti-drugs book ever written. In a way it debunks the stoned mentality for doing serious inner work. Nope, you have to get it straight from the source, not with anything else. Very serious read, but intense.
 
Aldous Huxley - The Doors of Perception -- At our age, a lot in this book still shines ... and shines ... and shines!
 
Herman Hesse - Steppenwolf -- It was a few years back a bit of an idealistic thing about something else, but when you read it now, it is something else. It is somewhat idealistic about the INNER trip, but it is very good. Also nice reading is "Siddartha", though I kinda think it is a bit preachy now. Steppenwolf is not. (AND, IF YOU CAN FIND IT, a guy named Fred Haynes did a movie version of this with Max Van Sydow, and various cartoons doing the philosophical parts, and it was great ... but way too out there!)
 
Aguirre, the Wrath of God - The film with Klaus Kinsky by Werner Herzog. Watch carefully to see how well it was coreographed to the music, specially the last 20 minutes. And the opening ... is a visual delight. The acting? Free form ad lib all the way through, just about!
 
Aria - A film with bits and pieces of opera arias done by various well known film directors, and you gotta love Jean Luc Godard's ... finger to the whole thing!
 
Magic Trip - About Ken Kesey and his Further trip. Make note of his editorial comments towards the end. The whole thing explains the "beat poets" so well ... and still makes me wonder why music can't do this!
 
Not Mozart - English crazyness and a whole bunch of folks doing Mozart in a way that you have never seen. The whole thing is insane inside out, but fun to watch. Peter Greenaway's opening thing is the best Bob Fosse you will ever see.
 
Prospero's Books - Peter Greenaway's take on The Tempest. If you ever want to really know what words mean, just listen with eyes closed to Sir Gielgud read this stuff and play the main character. It is simply insane, and the words are so crystal clear ... you never thought of Willy as that good, but it changes how you read him next time.
 
Have fun ... I'm done suggesting stuff out of left field ... anything else is too conventional. Or you can just enjoy another Harry Potter kitchen secrets book! I didn't even get to Italians, or Polish films (gotta see the double life of Veronique ... you gotta ... fantabulous music by Preissner)

 
Wait, I thought Pedro was our literary genius!

I think my fave book in the Culture series was Excession, probably as it's the most ship/Mind focused one.

I prefer Iain (M) Banks non-sci-fi personally ('The Bridge' is in my top 5 reads) but my friend is a voracious sci-fi reader and rates Banks' 'The Algebraist' as the best he's ever read.

I have not read any of Banks' Culture series. Is it necessary to read them in chronological order?
 
I am thinking of starting with Surface Detail because of its 80% 4/5-star reviews on Amazon, and because it's only $7.99 for the Kindle version. I'll pay more than that for a hard copy, but not for a medium that I can't pass along once I'm done reading it.