Hey, one of my Olympus buddies.
I am on a netbook at my DDs hospital bedside so bear with me.
My highest priority when buying a GSD is temperament. I want a stable temperament, because having a GSD without a stable temperament makes day to day life very difficult and puts everyone at risk. I want to meet both parents and see that they're friendly and meet the breed standard - cautious of strangers but not aggressive. One time when we drove up to the breeders' house, we got nervous when two huge GSDs ran up to the car barking. My DH rolled down the window

and the male promptly stuck a stick in the window for my DH to throw to him.
That was a stable dog.
I also want to see that the people I'm buying from have made efforts to "do the right thing" by their dogs, not simply breed for profit alone. For example, my current dog's father was certified as a Therapy Dog by Therapy Dogs International. That took a lot of effort on the breeder's part in training and socializing the dog. Both parents were also OFA certified, and although that won't guarantee my dog won't have hip problems, I know my breeder cared about it so hopefully the incidence of hip dysplasia is lessened, at least. I've had enough medical problems with my six GSDs to know that hip problems are not the only thing that can happen - one of my dogs was on wheels at the end of his life but his hips were great, it was arthritis of the spine that caused him problems.
So a lot to think about when looking for a dog.
Once you get the dog, get him out everywhere you possibly can, and enroll in a group training class - preferable one that goes long term. I like group as opposed to private training because your dog learns how to behave around other dogs as well as all kinds of distrctions. I personally would not do any type of Schutzund (?sp) training unless I was doing police work with the dog. I am very strict with my dogs that dog teeth can never go on human skin in any way; not playing games with my dogs that pit them against me (ie tug of war); and not letting anyone play rough with them. This has worked for me. My dogs know the difference between friend and foe and we do not have any "accidental" bites. This is important to me because I have a lot of kids and others coming and going around my house. As you know, there is a very strong herding instinct in some dogs, including the one I have now, who I had to teach to carry a soccer ball in her mouth when she's out with the kids as she wanted to nip their ankles - so now she "bumps" them with the ball instead and she's satisfied with that alone. (And now that she's older, she knows it's a no no anyway.)
Gotta go. Good luck in finding your dog.

(And want to see some puppy pics!)
These are all really, really good points! (and hope your DD gets better soon!

)
The only one I would disagree with is making sure the breeder has both parents on the property. In fact, having both on the property would make me look at them just a bit closer to make sure they are not backyard breeders.
Many of the best breeders will use AI to produce their best litters. If they used AI, that usually means they did a hard search to find the best dog in the country that would be the best fit for their *****.
So, if you ask to see both parents and they can only produce a vial for one of them, don't let it scare you away. In fact, you can be pretty sure that they wouldn't have gone through that much expense, it is very expensive to AI, if they didn't know what they were doing. Now, if they say that the neighbor down the street has the father and they just wanted puppies for the kids to witness the miracle of birth, then walk out right then and there
As mentioned, make sure you see either an OFA or Penn Hip certification for hips and elbows. Cerf for the eyes would be good too. Research what other diseases that GSDs are prone to and make sure that the breeder has tested for all of them. Again, a breeder who takes the necessary steps to make sure they are not carrying on genetic diseases is a reputable breeder.
Run, don't walk, if a breeder says it is not necessary to OFA the hips and elbows.The
German Shepherd Dog of America Breed Club is the national breed club for GSDs and has a link on its home page on how to find a reputable breeder for puppies.
They should be your first source in finding a breeder recommendation in your area.
And always buy a puppy from a breeder that subscribes to the ethics of the breed club.
Some of the other things a reliable breeder will do:
Many will not let you choose the puppy in the litter - they are experienced and will choose the best puppy with the best temperament that fits your family. This ticked me off the first puppy I bought, but when I saw how wonderful our puppy fit in our family, it made me realize, these guys are the experts. You don't want to choose the alpha puppy if you are a laid back family. You don't want to choose a more laid back puppy if your family is on the go all the time. A good breeder knows how to temperament test their puppies and put them in a situation that will be the best for the puppy and the family.
The breeder will ask you as many questions as you will ask them. This may be a pain, but it is a good thing. It means your breeder cares about where the puppies go and not just the money being made.
Make sure the breeder will be available for mentoring while your puppy grows up. They should be willing to answer questions you have about raising, training or health issues throughout the dog's life.
Make sure your breeder will take the puppy back no matter how old if you ever need to relinquish it. This is another sign that the breeder is doing this for the breed and not for profit.
My parents raised GSD's and I showed them when I was young, so they are near and dear to my heart. Wonderful dogs!!!