First, check all the local shelters and pounds. According to the Humane Society of the United States, 25% of dogs in shelters are purebred.
Contact National Breed Rescue Groups
If, on the off chance the breed you want is not available in shelters or breed rescue groups, buy your puppy from a responsible breeder. Responsible breeders only breed to improve the breed, never to make money. They NEVER sell to pet stores and RARELY advertise "puppies for sale" in the classifieds or on the internet, since they normally have approved homes for the puppies before they are born. They sell on spay/neuter or limited contracts so as not to contribute to pet overpopulation. Most responsible breeders are also involved in breed rescue.
"Backyard breeders" usually DO sell in the classifieds and on the internet. Don't encourage them by buying their puppies. Thousands of puppies and kittens are euthanized every day. Backyard breeders are a major contributor to pet overpopulation in this country. If we stop buying, they will stop breeding.
Many of those "free to good home" ads in the classifieds are there because someone neglected to have their pet spayed or neutered. If you respond to such an ad try to educate that person on the importance of spaying and neutering. Don't encourage them by adopting their puppies and kittens. These irresponsible owners are the number one cause of pet overpopulation and the mass killing of pets in this country.
Finding A Responsible Breeder - Myths And Facts
Email if you need help finding a breed rescue group or responsible breeder near you.