A frosted plastic box provides very nice diffused lighting - cut a hole in the top - put a box on with some scraps to level it so you are far enough away to use a standard lens - once you've predetermined your exposures it goes pretty quickly....The camera just sits over the hole in the box - no tripod needed and you can shoot straight down on the product...
Two most important things:
Daylight corrected light bulbs
A remote control for the camera. So you can do long exposures and avoid flash.....
Eben is right about shooting outside - open shade is awesome lighting - it's just cold out there a lot of the time.