Larry Barnowsky - 21st Century Coin Mechanics
Bert's Quarter Shrinking - Actual coins shrunken for sale 
Coinsgaff.com - A bit pricey but very nice coin gaffs. Todd Schoolcraft
Coin Manipulation - Descriptions and instructions for numerous coin slights
The Coin Purse - The premier coin site on the Web. 
Coin Trick Zone - The #1 site to learn coin tricks
Coinvanish.com - Dan Watkin’s contribution to the Web
Harrison's Magic Website - Coin tricks and sleights
Professional Coin Grading Service - The place to go to find out how much that coin for your act should cost you
Real Coin Magic - Gaff coin dealer plus a pile of cool videos to watch