We have 3 pet stores in town that sell balls.
The PetCo is new, clean and pretty nice. While the general staff don't like messing with the snakes they have an "expert", a little old lady that does care about the reptiles and snakes. Her knowledge is pretty wide with less specific "ball" knowledge and more general all reptiles and snakes knowledge. Their reptiles looks good and we have no problem with them. This is where we got Cleo, who is an amazing ball python.
The second is a general pet store, more fish than anything. They have a tank of balls that range from okay to poorish. The main problem they have is the substrate (coconut stuff?) which gets all over the snakes and makes them look messy. Some with less than stellar sheds. I wouldn't buy a ball there, but we do get our feeders there as they have a great feeder deli.
The third is a specific reptiles store downtown. They have a LOT of snakes and reptiles, I don't much care for their husbandry much. The balls are generally kept without hides, and a single heat lamp. Recently they are taking better care of them, in a newer enclosure etc. But we don't go there anymore mainly because the owner is a ****, way annoying personality and we just don't like dealing with him, rather than his store in general.
Within a couple of hours drive there are lots of reptile stores, and I mean a LOT. The best we have found is LLL Reptiles, they are about two hours from here and we think the drive is worth it, as there is really nothing to complain about with them, and lots to see and learn there. A+++!!++!++ Would do business with again!!!!+++111 (sorry got an attack of ebay feedbackitus) This is where we got Carmen.