The AKC is the only registry that does inspections, and many breeders had to leave it because they didn't pass. So they came up with the ACA, which has know links to puppy mills, and in my opinion is worthless. Please don't buy your pet from a petstore, no quality breeder sells to petstore, they are supplied by puppy mills. For more information on buying a puppy see this link from the Humane Society
Puppy Buying Tips