Hmm, for starters, I guess it's hard to beat free
So you might find VirtualDub (vdub) interesting, to begin with.
(I believe it appears in the Free Software Thread).

I haven't used any others, IIRC, so I can't give you first-hand info.

However, you can get a LOT of info and check out reviews at http://www.digital-digest.com/softwa...ategory-9.html

Good luck!