I guess, from a technical standpoint, This N' That (and Color Monte) don't use gaffs, since they are normal cards - but your point is still valid, robb.
One place to start, Jpoel, is Small But Deadly, by Paul Hallas. I reviewed it years ago:
http://www.talkmagic.co.uk/ntopic2369.php
It's a book devoted entirely to packet tricks. Not only does it offer a great history lesson, and some killer packet effects, it is a great resource to finding some of the better effects out there. One of my favorite books.
As far as sleight of hand-based packet effects, among my all-time favorites are:
Darwin Ortiz - Jumping Gemini
Capitulating Queens
Presto Printo
Queens out of Control
Twisted Sisters
Twisting the Aces
Cardboard Chameleons
Wild Card
NFW
Alex Elmsley's Dazzle - awesome effect
Hamman's Your Signed Card
Dr. Daley's Last Trick
Bear in mind, some of those use gaff cards, but that shouldn't turn you away. Dazzle is hard to come by, and uses gaffs - but it's a monster of an effect.
As robb said, don't discount the gaffs/gimmicks/self workers. There's gold in those, too!