Vash -
Check out this
site.
This is a well-respected German Shepherd breeder and trainer, including Police Dog and
Schutzhund, but his principles apply to all breeds.
Pour yourself a cuppa coffee and prepare to read -- this guy's got a lot of info on his site.
When the time comes, I'll be buying my Shepherd from this guy. The dog's name will be
Rommel. Certain to get along with Patton the cat.
JP