My partner is keen to get hold of some pre-sequenced versions of popular songs to layer his own variations over the top. I know absolutely nothing about music production or the software to be honest, but I have searched the web and forums to the best of my ability and haven't found anything other than dodgy Japanese sites.
 
If anyone can advise me if there is a specific format I should be looking for, or even better a specific website, that would be so great. He is using Sonar X2 Producer, but also has Sonar 8.
 
Thanks in advance!

There are general midi files of many pop songs that work in any DAW, including Sonar.  The file will default to TTS-1, but will sound better if you swap out with other synths.

posted wrong link by mistake:
 
http://www.hittrax.com.au...016&InetOrder=True
 

Here are some free sites:
 
http://www.cool-midi.com/
http://www.free-midi.org/
http://www.midiworld.com/
 
I have found and downloaded literally over 1000 free midi files, for all sorts of tunes, including even some progressive tunes, such as from Emerson Lake and Palmer, Genesis, etc.
 
Just do a Google search for: midi files download, and you will see all kinds of sites.
 
Bob Bone
 

helenmarks86
My partner is keen to get hold of some pre-sequenced versions of popular songs to layer his own variations over the top. I know absolutely nothing about music production or the software to be honest, but I have searched the web and forums to the best of my ability and haven't found anything other than dodgy Japanese sites.
 
If anyone can advise me if there is a specific format I should be looking for, or even better a specific website, that would be so great. He is using Sonar X2 Producer, but also has Sonar 8.
 
Thanks in advance!

Finding quality MIDI files for free is hit and miss... mostly miss.  I create backing tracks for my live show and the best quality source is  www.midi-hits.com.  They'er not cheap - $8.99 each but they are professionally done with e-drums, MIDI guitars and  keyboards by professional players.  They have thousands of titles.