I think most feel that way at one time or another.
I know whenever I am about to get a new puppy, I question my decision, in the end it all works out ok
I do think with the net and all, one looking for a dog can become over frazzled by ALL the websites, this, that, who to pick? what if I'm wrong? Sometimes we can overload information when it can be fairly easy.
Do you know anyone with a german shepherd that you really like? Ask where the dog came from..
Find breeders you can visit! And VISIT, see their dogs, meet them..
Any shows around? Check them out..
Key is knowing what you want and don't want in a dog, and then finding a breeder who can match you to that perfect puppy...