Very good of you to research before you buy. I would take a look around this site and read about the different set ups. Ball pythons do much better in "tubs" as you will see them called. Its a simple plastic tub from walmart or target etc....
I started with a 10 gallon glass tank, but very quickly decided that the tub route was going to be much easier. I had to have a heat lamp and that took all the humidty out so I was misting two-three times a day...very annoying.

First off check out these links

Here is the Ball Python Care Sheet
http://www.ball-pythons.net/modules/...warticle&id=59

This is a nice write up on humidity
http://www.ball-pythons.net/modules/...warticle&id=33

Here is a very do it yourself for a tub set up
http://www.ball-pythons.net/modules/...warticle&id=40

Those are some good places to start.

I would suggest you also check out the morph list here
http://www.worldofballpythons.com/morphs/

I would figure out what all you need for your set up...glass tank or plastic tub. Get every and get it set up. Get the temps and humidity running smoothly. Then find what morph you REALLY want (do not settle because then you will end up a few snakes...) trust me it is addiciting!!
Once you really figure out what morph you want to look at for the next 15-20 years go to the SLC show and get one. Right now there is going to be slim pickings due to being the end of breeding season and people are just getting eggs. It 90 days there will be a ton of hatchlings out there to buy.
I can say in your price range the tub set up is much cheaper and normally easier to care for. Your not going to leave yourself much if you do not wait. Just make sure your happy with the morph you pick because the more your on this site and the more pictures you see the more you will want it if you do not get it up front.