eBay Auctions (Mint Errors)
The largest auction site featuring mint errors. I place many errors up for auction.

ANACS
One of the largest coin grading and authenticating services. ANACS has been certifying mint errors for nearly ten years. They were the first major grading service to encapsulate mint errors.

CoinFacts
The internet encyclopedia and price guide of United States coins. A great resource for information on mint errors.

Error World (Yahoo Club for Mint Error Collectors)
Join the hottest club on the web for mint error collectors.

uspatterns.com
An interesting web site featuring United States Patterns, Die Trials and related rarities.

Byers Numismatic Corp.
The Largest Dealer of the World's Rarest Mint Errors. Their premier MULTI-MILLION DOLLAR INVENTORY includes only the best, museum quality, world class and exotic U.S. and World Major Mint Errors and Die Trials.

Coin World Online
The largest numismatic newspaper in the industry. The latest news and discoveries on mint errors can be found here.

CONECA
The Combined Organizations of Numismatic Error Collectors of America.