In the past I've seen them offered for sale by Signal Herps (as was previously mentioned), Herpetological Breeding Research, and Radical Reptiles. You can also still see the occasional LTC for sale on the classifieds forum here. If buying one of these I would be wary and ask LOTS of questions.
As for biting - I'll agree with the other posters. They all definitely have their own personalities. I would say that in most cases though if you spend a good amount of time handling the animal it will eventually get used to you. I don't regularly handle mine at all (they're to look at, not play with at my house!), and I have 1 that jumps at me every time I reach in the cage, trying to bite me. One is fairly indifferent. And 2 of them charge out the door trying to climb up my arms and just get attention. Those 2 were both hand raised by other people when young and got plenty of handling. I've had one for 4 years, and the other for 1 1/2 years, and both are still quite tame without any regular handling.
They are definitely intelligent and fascinating animals, but they do require more work than most other herp pets. Daily or every other day feedings, water changes just as often and poop pickup daily as well. Combine that with the 1-2x/day mistings and you're looking after them at least once daily at a minimum. It's more time consuming than cats, not quite as time consuming as a dog.
As long as you have the time, the desire and the money to pay for their large enclosures, humidifiers, bags and bags of produce and the occasional vet visit, you should do fine.