To get the best recommendation it would help if you could tell us a little more about yourself and what you are looking for in a GSD. American lines or import. If import are you looking for a working line breeder or show line? West German or DDR/Czech? Any strong preferences as far as color and appearance?
Have you ever owned a GSD before? Are you interested in doing schutzhund/obedience/agility/SAR? Do you have kids? Other pets?
I know this can seem overwhelming, particularly if you are a first time GSD owner and just want a healthy dog with a stable temperament that will make a good pet. But there are a wide range of breeders, who have differing goals and use different lines. A lot of it is matching the right breeder to the right person.
For example, I have some familiarity with Abby Kennels. Visited the kennel, met one of his stud dogs, saw a couple of older puppies and know someone who has one of his dogs. A lot of the people who own his dogs do Schutzhund or fairly serious obedience training and he has some great dogs. But I'm not sure his puppies would be a good fit for a first time GSD owner with kids who doesn't have the time or the inclination to get the dog involved in some kind of training/work.