Depends on the size of the incubator you want.  AP sells a large one that's really nice here's the link, just scroll down the page and you'll see it.

Now that's out of my price range for now, so if you're like me I'd go with either Exo Terra's or Zoo Med's.  Now if you're really on a budget I'd get a Hova-bator.

Hope this helps.

I just ordered a cheapy hovabator from LLLreptile. I don't expect it to be the best investment, but I need it on short notice and it'll get the job done. The reviews on it are hit and miss. Some people LOVE it, and other HATE it. Theres no inbetween.

LLLReptile.com has a special right now with the Hovabator, hatchrite incubation bedding & deli cups for $50

The AP incubator is rad. If you need something smaller/cheaper you could try these:

Nature's Spirit (I had this incubator and it rocks) - http://www.nsreptiles.com/incubator.html Not sure if they are back into selling them but maybe, worth a shot.

Otherwise, I'd really say giving a shot to building one would be worth it. Get an old freezer or fridge, the rest is cake after that. Really not much you can mess up honestly ;) if you feel uncomfortable with wiring heat stuff a lot of places like Reptile Basics will wire heat tape for you.

make sure you just hook up a good thermostat to the hovabator for ball python eggs

http://www.reptipro.com/reptile-supplies/incubators/reptipro-6000-incubator.html

You'll thank me later.

forgot to mention has a cigarette lighter A/C adapter for the car so you can transport without losing temps.

Thank you all for your help :D