|Light fixtures can be expensive or ... you can "do it yourself"
Wall Mart reflector $6 , and use something heavy to clamp it to while on the desktop - a brick works well, I use an old microphone stand. (mic-stand also about $8 from Radio Shack)
Look for light reflectors that are white or silver (avoid colored reflectors!)
Wall-Mart, Target, Big Lots, K-Mart ... etc. etc.
Buy table top tripods with reflectors on E-Bay. (Watch out for shipping cost!)
The key to all of these is to get the correct 5000°K fluorescent bulbs. I prefer the spiral bulbs (sometimes called "trumpet" bulbs - spiral changes size) as they put out more light in a forward direction.