The decision to bring a puppy into your home should not be done lightly. This will be a lifelong commitment to this dog. Finding a breeder is a very important part of process. I often tell people it should be as much of an interview for you as it is for the breeder. You should plan to have a relationship with that breeder for you the rest of your puppy’s life, so it’s important to feel comfortable with that person. Your breeder should be resource for you, be there to support and help you with any questions you may have about your puppy.
A reputable breeder should be familiar with the breed. They should have some affiliation with their breed club on a local and/or national level. They should do health clearances on all their dogs. They should allow you to see where the puppies are raised and to meet at least the dam of the litter. They should not encourage you to purchase 2 puppies.
You should NEVER purchase a dog from a pet store. ALL dogs in pet stores come from puppy mills, no matter what the store clerk may tell you. No reputable breeder would ever allow their puppies to be sold at a store. Puppy mills do not breed for temperament or health. So while you may save some money at the purchase time, you may end up paying for it in the long run. You also open up a space to be filled by another puppy mill puppy, keeping these terrible people in business.
Just Weimaraners has an excellent article on how to find a reputable breeder, which includes a checklist. It’s worth taking the time to review this information carefully.