Ok, I must be missing something obvious here.  I'm using Sonar X3 Studio.

I have a tune, I wanted to add a military snare drum in the background, and found a free one online.  It's at 120, I need it to be at 100.  I tried Fit to Time, but that goes by time (obviously), which doesn't help.  Is there some tool I'm not seeing that can do this?
 
Thanks!

This clip you found online, is it a midi clip, an audio clip, a groove clip, or something else ?

Sorry, I should have stated that.  It's an audio clip, .wav format

Maybe audio snap is place to start?

I think you're right!  I'm starting work on it now, will post back.

Ok, well that didn't work.  Either I don't understand how to use it properly (most likely scenario) or it's not meant for that.  I tried editing the tempo map of the clip, then cutting and using the portion I had done, and it didn't work - even when I enabled "clip follows project".
 
I've just opened up a new song, and imported the clip to that.  I'm going to try and figure this out, if I can.  Any suggestions are much appreciated.  It should be simple, what am I missing here?

Ok, final update.  I inserted the clip into a new song, set the tempo for 120 (same as the clip).  Edited the clip tempo map in audio snap to line up with the quarter notes of the song tempo.  Then, I lowered the tempo to 100 and set audio snap to "clip follows project". 
 
Worked!
 
I then exported it, and imported it into my project.  A few of the bits didn't line up correctly, probably because I may have stretched the audio when moving some of the transient points (this happens if you drag a point from the line instead of the little diamond shaped head in the middle of the line).  Oh well, fixed it all up.
 
Now to see if it was worth doing in the first place!
 
If anyone can make a suggestion as to how I might have accomplished this more easily, I would appreciate it. Remapping the tempo took quite a long time, partly because I didn't know enough to use the Resolution drop-down list in the AudioSnap palette, which would have cut out a lot of unwanted transients.
 
- Russ

realex
If anyone can make a suggestion as to how I might have accomplished this more easily, I would appreciate it. 

 
Option 1: Highlight the clip and type Ctrl+L. That might work. If not, then you need to learn how the Loop Construction window works, so instead you might want to try...
 
Option 2:
 
1. Load the wav file in the 100 BPM project so the beginning starts on a measure.
2. Hover the cursor over the edge of the clip while holding Ctrl until the edge has a yellow line.
3. Click and drag outward until it hits the right number of measures in your project, e.g., if it was two measures at 120 BPM, stretch it so it's two measures at 100 BPM.
4. You're not done yet. Click the clip and select Clips > Bounce to Clips. This is necessary to switch from the low-res preview algorithm to a high res stretch algorithm that sounds a lot better.