There are plenty of inexpensive light box kits that come with non-reflective backdrops (in white, black, blue, and red, for example) available for purchase on eBay. I mostly use the light box kit, plain white copy paper, or a specific green place mat. You can also purchase a large white piece of foam board and cut it up to make a simple, cheap light box and backdrop. There are some easy DIY light box tents online.
