Try a hobby store. I got a loupe that has both 20x and 30x for about $20. I also have the 60-100x microscope that dutch pimp just recommended, although i find it very troublesome to use and prefer a 30x eyepiece.

DON'T buy the 30x jewelers loupe from eBay. I bought 3 of them for friends and when they came in, i was glad to see the lens was much larger than my 30x, but the magnification was 15x at best and you can't see the colors of the trichs. NOT AS ADVERTISED...

it's worth the money to get a good one.

Skeet.