Best way to convert or quantize real drum tracks

it depends, if you want to keep the original drums you have recorded then no, Autosnap is the best way to go.
it is very time consuming and tedious but it works. 
 

Audiosnap is the best way to go. There is an old post by Lord Tim that gives a very good work flow for doing this. Do a search for it and you'll find it. 
 
Basically it outlines how to take a snare or kick track, copy it, use a very aggressive gate on it, so aggressive that it only leaves a blip for the hard hits. You'll now use this track as a guide track to accurately get the transients across all your tracks. Audiosnap doesn't really do a very good job so getting this track right is imperative to getting a good guide track with accurate transients identified.
 
Then turn transients on for all the tracks, set all the other tracks to 100% so NO transients are shown. Set the transients on this guide track to something sensible, maybe 50% or so to get the transients desired.
 
Manually make sure you have all the transients you want showing on the guide track. 
 
Then merge and lock the transients from the guide track across all the multitrack drums. You'll then have to unlock the tracks so you can move them. 
 
Now you can select all the tracks (a track selection group helps here) and manually move the transients across all tracks simultaneously to align them with the grid how you like. 
 
It's a tedious process, but works wonders. If you also want to overlay drums from AD2 or Session Drummer, you can use the guide track to copy the midi notes and overlay a snare or kick (whichever track you used) or use the same gating technique to create midi notes for other drums. 
 
gabo

Thank you guys.  I will search for that post
 

I didn't go find Lord Tim's post. But I did find that I had copied the note and put it in a safe place on my computer. So all the credit for the following goes to Lord Tim! I just cut n pasted it from his post so these are all his words!
 
I will say that I have used this method and it works very well. The only change I have made to it, is instead of adding the transients to the pool, I just merged and locked the transients across the tracks. Either way works just as well.
 
1. Record the drums (duh)

2. Find out which tracks are the main timing guides - usually kick and snare tracks. Clone them.

3. Solo the cloned tracks. On the clones, you want to aggressively gate the hell out of them so you're just getting the initial pop on the start of each hit and nothing else - the track has to be completely silent between hits. It'll sound like garbage, but that's not the point - we're not going to be using these for anything other than our timing guide.

4. Bounce those gated tracks to a new track. That's going to be your guide track now. You can either mute or delete those original cloned and gated tracks now.

5. Enable Audiosnap on all of your tracks, including the new guide track. On the Audiosnap palette, drag the Threshold slider all the way up to 100%. This will make every transient on all of the tracks disappear.

6. On your guide track, lower the Threshold until you get a useful amount of transients turn up. If you're lucky, they'll be on every hit, and if you're even more lucky, you won't need to go in and manually move anything to be on the beat and you're good to go.

7. More than likely things will need adjusting, so zoom in on your guide track with the transients and move, add or delete transient markers until you have one on every hit. Getting your guide right is crucial to this all working well.

8. Right-click the guide track, go to Pool > Add Clip to Pool. All of the transients will turn blue, telling you they've been added to the pool.

9. Select all of the other drum tracks, right click on any one of them and go to Pool > Apply transient pool markers. You'll see transient lines appear on all of the clips that line up with the blue transients in the guide track.

10. Select all of the tracks (including the guide), right click any one of them and go to Quantize and make sure Audiosnap Beats is checked. Quantize to taste.

That should get you 95% of the way there. Mute the guide track and listen back - has the quantizing put beats in the wrong place? You need to go back and manually adjust things. Turn your Snap on, find the beat that's not correct, left-mouse lasso around the transients that are on the wrong beat so they're selected across all of the tracks, and drag to the correct position.

All where it should be? Great! This is using the Online stretch algorithm so it won't sound amazing, so you'll need to bounce all of the tracks to new clips so it uses the better quality Offline algorithm. Delete the guide track and you're done!

Things to consider:

This is locking things up pretty tight. If you don't want things quite as tight, you can play around with groove quantizing and things like that. It's fiddly and results are honestly hit and miss.

The reason I went to the trouble of making these guide tracks is because transient detection currently sucks whenever there's any slight bit of noise other than what you want to detect on a track. It's almost to the point of being unworkable, in fact in the past I've gone through and manually placed transients because it's been quicker doing that than fixing all of the wrong ones SONAR has "helpfully" put in for me. The guide tracks cut out a LOT of unwanted track bleed and DRAMATICALLY help the detection algorithm.

If you need timing from something like a hi-hat or an overhead mic or something, honestly, save yourself the headache and manually put transients in. It'll be about as much work doing that as fixing SONAR's mistakes and you'll likely do a better job at it. 

HighAndDry
I want to get good at using real drums and converting/quantizing them etc.  

this is a major contradiction in itself.
 
if you want to get good at using real drums you should not use any quantizing at all. it will just ruin it all.
 
get a good drummer, learn how to properly mic a drum kit so you can comp multi-tracked takes, etc ...
 
this is time consuming and expensive (mics and room) and will take a while until you can match sound quality from today's sample libs.

Recording now a days is about correcting bad performing musicians, Drum replacer , melodyne ect ect.
The worst part of it is that you don`t even tell them about it cause nobody does.
If you do tell them you`re out of business.
I am not talking about maybe 3 to 5 kicks in a 3 min song,cause in that case I would just correct them with my ears,but a whole song keeps going in and out off timing.
How sad.
Peace

maltastudio
Recording now a days is about correcting bad performing musicians, Drum replacer , melodyne ect ect.
The worst part of it is that you don`t even tell them about it cause nobody does.
If you do tell them you`re out of business.
I am not talking about maybe 3 to 5 kicks in a 3 min song,cause in that case I would just correct them with my ears,but a whole song keeps going in and out off timing.
How sad.
Peace

that's generally a sad thing today - relying way too much on computer technology and assuming upfront that it will fix things in the mix ...
 
of course, I'm also guilty of heavily melodying vocal performances so I did not have to upset the "artist". yet these are (hopefully were) the mixes I hide deeply in the archives
 
meanwhile I started to think differently and give a lot of honest feedback. I also ask people to come back later once we did listen together to the first takes. but really I rather work on the performance over a couple of tracking session and do a lot less editing on the final takes, than track quickly and spend hours editing (fixing poor performances is the most boring part of the entire game IMHO). practise gets you so much further than melodyne & co and most musicians are very thankful for quality feedback. I have been surprised many times that even people who were performing live for a decade rarely ever got honest feedback ... and usually they do appreciate that a lot.
 
 

drum replacer works great for something's.
however it uses SFZ files like the ones that come stock with Sonar + DR from Chocolate audio.
they are multi layered samples. so if one wants to use their own samples they need to create an SFZ file, though I haven't tried this yet. I know you can drop a regular Wave file in to DR I believe but if you want true velocity scaling, you need SFZ files.

Thank you gbowling!!!

HighAndDry
Thank you gbowling!!!

You are more than welcome. I've spent many hours doing this and others on here helped me get it all worked out. So I'm just passing it forward. 
 
gabo