There are a huge number of suppliers. boaphile, animal plastics, vision, and the 100s of others I failed to mention. I tend to try to buy local personally so I buy from local producers.
There is an other idea as well. the problem with tanks is the open top heat rises and humid air rises and the top lets both out. rather than restrict air flow to hold in heat and humidity turn the tank.
http://ball-pythons.net/forums/showt...arium-Solution