I'd like to connect my ps3 controller to my arduino with the USB cable. Is this possible? I assume there's got to be a library out there...
You'll need a USB host shield. The CircuitsAtHome shield has a PS3 controller library.
And where would I find a schematic for such a shield?
By following the Schematic link on the first link I posted?
Oh, there it is. It was broken before.