Start with Michael's suggestion, it's where I started too...
Alf Lovvold did a great tutorial from his awesome short on masks and tracking found here:
http://www.alflovvold.com/tutorials.htmlThere's also a few good ones with a "fusion rotoscoping" search in google. A lot of them are from Fu6, but they all pretty much apply the same in 7.7, not sure in 8 (haven't used it yet) but i'm guessing they do.
Quick tips: use "t" for twist, "s" for scale, alt with a point selection for x,y movement.