Hi and welcome! I split your post off to make you your own thread, I hope that is okay. Are you meaning turtles or are you meaning tortoises, as some folks call tortoises turtles?
Welcome! I'd do some research on each species and find which suits you and your area best. Having said this, I own two Cherryheads in NY...so don't let climate be the determining factor.
Sulcatas and Aldabras get big.
Russians, leopards, redfoots, and greeks remain a bit smaller, but are still sizeable.
Tortoise supply is also a reputable breeder and there are numerous reputable breeders here on the forum if you don't find what you're looking for at the reptile show.
It would be a good idea to learn a bit about each type of commonly kept tortoise before you get one and end up with something that doesn't fit your lifestyle.