I have had a pretty good time at every snake show I go to, even if I don't get to buy anything. If you find someone passionate about what they do and it's not too busy, you can get some pretty good 1 on 1 time with them. Ask questions about the animals, it can't hurt to learn something. And I have gotten some awesome deals by talking to people. Most people are willing to negotiate on their prices. I have never seen a firm price.
One thing to watch out for, mites or sick animals.