redearslider.com

If this site has been mentioned before, I'm sorry and please disregard. But someone I was talking to online recommended this site to me and they have the reptisun 5.0s at a really good price. I didn't look at the rest of the site, maybe they have more good deals on there. I have yet to use the site so I don't know if it's reliable. But it looks like a good deal.

http://www.LLLReptile.com

Yup, I've bought from them before and have been very pleased with their prices and service. I haven't got any live animals from them but they do have some interesting ones for sale from time to time too.

Some other good ones I use are:
http://www.bigappleherp.com
http://www.reptilesupply.com
http://www.petwarehouse.com <-- aka Dr. Fosters and Smith

I've dealt with them as well. They appear to be quite reputable.