Do you live in NYC or in the state? If you live in NYC and have a 5 year old, I wouldn't recommend a GSD. You'll need to spend lots of time getting out and exercising and your son may take a back seat to the dog, which would be a conflict as most people put their children first. An older child who could take on some responsibility would be OK, IMO.
There is a member here who doesn't sign in that often that may be able to help you, he lives in Long Island and has beautiful dog, here's a link to his last post and you can try to send him a private message:
Kira says Hello!!