As posted by Shuggie:

This is the best guide to Audio Sync problems I've ever found

http://nickyguides.digital-digest.com/audio-synch.htm

It contains a utility to fix AVI files which are out of sync. However - it does so by changing the framerate. If you want to eventually convert to a format with a specific framerate - you'll need to stretch or compress the audio, and for that you'll need something like cooledit.

It's an excellent guide and well written for the non-expert (like me!)

HTH

Could I encode the *fixed* avi to Mpeg with TMPGEnc? Just wondering.
Thanks.