I'm new to Sonar.  The sales brochure said AudioSnap would help sync midi drumtracks to MP3 files, but I struggling to get it right.  Is there any chance someone could help me please? These are the steps I making:
a. already have mp3 and midi drum sequence loaded.  Both play OK, but not in sync.
b. Using AudioSnap, I think I two choices - quantize the MP3 file, or extract the groove and apply to drum track.  I think the extract groove approach sounds best, but how do I apply the groove to my midi drum track?
 
I'm stuck.
 
R.
 
 
 

I use a manual method where I adjust the tempo until it lines up. Start with a four beat count in. Line up the first beat of both the audio and the midi track. By changing the tempo get those four beats lined up close as possible and then check the end of the song.
Start changing the tempo by finer amounts.  
Example 123.21 BPM until the start and finish line up.
This works perfectly for audio tracks that were recorded using a steady tempo which I find is 80% of modern material. 
If this doesn't work go to plan B which I'm sorry I have never used plan B. 
 

This article elaborates on the technique Cactus Music describes. Also bear in mind that AudioSnap is not optimized for program material, but for individual tracks (preferably percussive).

When I have to sequence an MP3 file to a MIDI file I have a formula that I use to get the tempo.  What I do is get a given number of beats and the time in seconds that number of beats occupies.  Then I convert this to tempo in BPM. 

The formula I use is as follows:

(60/S) * b
Where:
b = number of beats
S = Number of seconds that those beats occupy

Even doing this you will find that some MP3 files tempo does drift so you might have to do this further into the track to get the tempo back in sync.   I know this is a long method, but it's consistently accurate.

I have even written a small VB program to do this calculation though it would not be hard to write a CAL script.  All I have to enter is number of beats and seconds.

To be honest I think this whole process is needlessly complicated in Sonar, considering the state of modern beat detection tech. If you know your music theory and enough about Sonar it's not exactly difficult but still pretty involved. I hope there can be some improvements in this area.

Anderton
This article elaborates on the technique Cactus Music describes.

Craig, on reading this article, my one thought was that you don't need a controller if you have a touch screen when writing out lyrics.