Research your chosen breed and the various types and lines and ask yourself which type best fits your family and if you have the time and space to dedicate to training and exercising your dog. German Shepherds, for example, are an intelligent breed that love to work for their handlers and need lots of exercise.
Visit obedience, agility or Schutzhund trials to meet dogs and their handlers, these people can often recommend good breeders. People who spend time training and exhibiting their own dogs are usually the most passionate and caring about their dogs and their breeds.
Find out which health tests are recommended for your chosen breed, a list of these can be found at the Canine Health Information Center - http://www.caninehealthinfo.org/breeds.html
When choosing a breeder, ask lots of questions, if the parents have been health screened and titled. Ask if the breeder themselves titled the dogs. Ask the breeder what they do with their dogs and what their breeding goals are. Choosing the right breeder requires time and research, but is crucial to ensure your future dog is healthy, stable and a good fit for your family. Be prepared for the breeder to ask you lots of questions about your plans for the dog, as well as experience with previous dogs and living conditions.
In our opinion, the best breeders are those which have a maximum of 2 or 3 females at home though they may lease or have other females who are trained by others. Their females do not live full time in a kennel, and are not bred on every heat cycle. We choose breeders who spend time training and then proving their training by gaining titles in a performance arena. These breeders know their dogs' strengths and weaknesses and usually know enough about dogs to be able to recommend the right puppy to each buyer. The best breeders may recommend another breeder or even a different breed, or an adult dog which will fit your requirements better.
Breeders who import or buy titled dogs are probably trying to do the right thing, but cannot possibly know the dog in great detail unless they continue it's training further. Many adult "import" dogs are not superior to dogs already in the USA, in fact, they are often sold out of Europe for a reason, and it can be because they are not good enough to stay. We are also wary of breeders who always use their own or one local male for stud on all their females, how can this one male possibly be a good match for all their females?
A guarantee from a breeder does not mean your puppy will not be dysplastic or have other problems. It usually means that the breeder has some sort of replacement policy. Think about that for a moment, you raise a puppy until 2 years and now it has bad hips, are you willing to give that dog back to a breeder and get another puppy? The dog you just gave back could go to a pet home or could be put to sleep. The replacement puppy will probably be from similar lines and has a chance to have that same problem again, then what? Or do you keep the original dog and spay or neuter it, then pay less for another puppy, now you have 2 dogs, do you have the space, time and money for both of them?
Guarantees have to include a lot of detail to protect both the breeder and purchaser, and are subject to abuse on both sides, most buyers cannot reasonably complete all the requirements to ensure the guarantee stays valid and many breeders don't honor their guarantees.
Having said all this, please remember that a dog is not a machine and even the very best breeders can only do so much to ensure their pups are healthy.
Currently the going rate for a good prospect for sport is $1500 - $3000. This is likely to be a "working line" german shepherd. Working lines are typically higher energy and more driven and they will need obedience training and preferably a "job" to do to keep them engaged. A "show line" german shepherd is likely to be $2000 +, maybe a lot more for an excellent showing prospect. Show lines are typically black and red with medium energy and drive, they still need training and a "job" to do, but may be a little easier to live with. Obviously these are gross generalizations and individual dogs will vary as far as drive levels, an off-switch and ability to compete.
We recommend that you find a club BEFORE you look for a puppy, you can see which club members dog's appeal to you the most and they can recommend good breeders where you can buy a puppy to fit your needs and budget.