LINKS:
Here are some excellent resources for the arcade homebrewer:
(I'm guessing the majority of visitors already know about these)
Build Your Own Arcade Controls FAQ
MAMEworld
Game Launcher (the best front-end ever!)
Daphne
Happ Controls
Dragon's Lair Project
Ulti-Marc
Druin's Rotary Joystick Interface
T-Molding.com
Roto-Zip Tools
Shopsmith Tools