Greetings--
 
I have some old stereo recordings I made many years ago and I'd like to load them into Sonar and add some other instruments, especially drums. My problem is that I can't figure out how to teach Sonar where the beats are. When I let Sonar try to identify the transients, it can't really pull it off. 
 
I thought I might record a second audio track in which I would just tap the beats, but then how do I tell Sonar to use that tempo? 
 
I don't want to stretch/shrink the music to fit Sonar's tempo (like Audiosnap would adjust a sloppy performance to fit its tempo), but rather have Sonar adjust the tempo to fit what is already recorded. 
 
Oh yeah, I'm in platinum.
 
Any thoughts? Thanks!

Yes, you can build a tempo map that SONAR will follow by getting it all set up and using the "Project follows clip" option in audiosnap.
 
I'm not at DAW right now, but you activate audiosnap on the clip, edit the tempo map, and use Set Measure/Beat at Now to define your map. The more you do the more SONAR will start guessing the right tempos.
 
Do a good forum search, I think FastBikerBoy did a few detailed explanations of how to do this.
 

Thanks Wicked. That gets me started.

If you want to use the original tempo and timing you can just right click on the timeline and select Insert Beat/Measure from the dropdown menu. A window will pop up with Sonar's best guess at what on what it should be and you can edit it from there. I did this with some live tracks from years ago and although it is tedious it's pretty easy.
 
All your changes will be reflected in the tempo map so that way your click track will follow the nuances of the project as will any MIDI input stuff.
 
If you want to correct the tempo then yes... that would be a job for audiosnap but is far more intensive of a process/learning curve. There are some vids in the CakeTV section on working with audiosnap (one of the CakeTVLive episodes on drum production covers some of it) and those vids I pointed you to earlier (the X2 vid) has a pretty good description on Audiosnap.
 
Cheers.

fastbikerboy did the definitive tutorial on this.   youtube has it.

Oh... I forgot to mention for the Insert Beat/Measure thing I think you have to set the Now Time to where you want to insert your time change. It's been a while so I'm a little fuzzy on the exact details but it was really easy.

What the other guys are describing and what Karl "FastBikerBoy" shows in his vids is how to edit the tempo map of a clip which is useful for many things but if I'm reading your OP correctly you just want the project tempo to match your tunes. Editing the clip map is more of a PITA and unnecessary for your needs. I'm not at the DAW right now otherwise I'd double check and post more detailed instructions but try out what I posted AND check out the clip map editing to see what best serves your needs.

I'm not at my DAW right now, but I think you want "Fit Improvisation". Basically, you import your audio files into Sonar, create a midi track and record 1 note for each beat of the imported audio. Then you select the midi track and choose "Fit Improvisation" which will create the tempo map for you from the midi note timing. The more accurate you are with lining up the midi notes with the imported audio beats the more accurate the tempo map will be.
 
Here's the info from the manual:
 
http://www.cakewalk.com/Documentation?product=SONAR&language=3&help=EditingMIDI.39.html#1419292
 

The problem I find with all this autodetect stuff is no matter what if you want it to be truly accurate you are generally going to have to go back through and correct things which even at the best of times is going to be almost as tedious and painstaking as doing it manually from the get go. If you are going to have to go through everything anyway then why not just get in there and do it one measure (or even one beat) at a time and KNOW that it's done right?
 
However the auto detect stuff works best on this type of live material when you split the tracks up into sections. That way instead of the detection algorithms having to find an overall tempo for a loooong out of whack performance which inevitably results in out of whack and erroneous assumptions it is working with smaller, easier to manage chunks. It ends up being more accurate then you can send that to the timeline section by section.
 
I still say that there is no need to go into the clip tempo map for the OP's needs and then translate it to the timeline. He just wants the project timeline to match the audio. No clip tempo editing needed. Not sure but I think from there he might be able to snag the newly created tempo map and apply it to the overall clip (so in reverse) if he wanted to screw around with it as a groove clip but I'm not sure about that.

I think Beepster's recommendation is what the OP is seeking... a simple tempo map set to the imported audio track.
 
Quickest method is to count beats for 10 or 15 seconds and convert that to a rough bpm, and open a new project and set that bpm. Import the audio track. Next align the first beat to the third bar (I try never to butt the beginning of a song to the left edge), set the now time on that beat and hit "Shift-M" to assign it exactly to the bar. Start following the song and as it drifts on a beat, align the now time, Shift-M, and assign to where it should appear. What SONAR does is create a tempo map for you (the audio is unaltered). This is important to align MIDI properly to a pre-recorded audio track.