Having issues for the first time in doing this, I've never had to deal with "drift" until my latest recording. I see that calculations spreadsheet posted, and I have no idea what I'm looking at there. Is there a simple (like I'm a 5 year old) explanation, or any other alternative methods, programs, etc?
The easiest way is:
1) Trim each source so they start and end on the same sound (start of a drum hit, guitar strum, anything well defined)
2) Select one source in its entirety and write down the endpoint (second number) under Selection
3) Select the other source in its entirety and select Effect > Pitch and Tempo > Change Speed and Pitch
4) Change "New Length" to the length of the first source.
If it still doesn't sound right, eyeball the two waveforms near the start and end — you probably messed up Step 1, which is easy to do, so go back and try that again, then redo the other steps.