I already had my desk light from a while ago, but you can find them at Walmart and maybe shopping stores. Some hardware stores have them as well. If you want to do low cost, I went to my local hardware store and got a 15watt GE 6500k bulb for $7, then you can get one of those heat lamps for reptiles at the hardware store (only difference is that instead of the reflector on the outside being black it is metal) that is like $7.50. I like the look of a desk light more though.
15 Gallon NPT
1g no tech bowl in the making