The 'big breeders' are very professional and super-safe (if you're buying a het especially).
Some of the smaller breeders are awesome too - I've found calling folks and asking questions is very rewarding. The breeders who love the critters are happy to spend time telling you about their babies (or older snakes).
When I start to produce, ALL my recessive projects will have at least one visual parent. That way you take the guess work out of the equation.