I was using FreeDO, a 3DO emulator the other day and realized it did not work with my cheap Logitech Precision gamepad. I searched online for a good keybinding program and came across:
http://www.xpadder.com/
It’s a free program that lets you import a pic of any joystick and then create buttons, triggers, analog, D pads, etc in a joystick editor. You can then add any keyboard functions to these keys and save the profile you create. Their editor is really sweet and makes it so you can create virtually unlimited variations of gamepads. (Even ones that do not exist)
This really improved the gaming experience on Emulators lacking good gamepad support.