Re: training a GSD??? HELP PLEASE!!!
I'm glad you've put the dog back in the house. I know my pup hates even being apart from me when I'm in the bathroom showering; I can't imagine how he would feel living his life outside, constantly away from me.
Your problems with your dog may seem overwhelming, but they are actually relatively minor.
1. Your pup is still pretty young, young enough that he might still have puppy phases in which he does what he wants when you want him to stay. Have you taken him to obedience classes? Those help a lot. Also, be patient. Remember, Rome was not built in a day, and the same is definitely true with dog training. Teaching your dog stay takes time and patience. I've been working at it with my boy for a few months now and he still sometimes breaks stay when he feels like it.
2. If you don't want your dog to sleep on your bed, don't let him on the bed. Is he crate trained? If not, teach him to enjoy the crate as his "den" and make him sleep in there.
3. My dog doesn't naturally fetch either; he's a shepherd, not a retriever! If you want to teach him to retrieve, put him on a long lead, throw the ball, encourage him to get it, and reel him in while saying "Fetch!" or whatever command you want to use once he has it in his mouth. Then praise heavily once he gets back to you.
4. GSDs are naturally aloof, and if they are bonded with their owners, will show their protective instinct when the need arises. I assume the people your dog comes in contact with do not pose a threat to you, so it is perfectly acceptable for him to be friendly towards them once you have deemed them "friends." The other side of the spectrum would be your dog growling or snapping at strangers, in which case you would have an aggressive dog on your hands, which is a huge problem. At least your dog is aloof! My pup still rolls over on his back for every single person he meets, stranger or not! Also, I find that merely having a GSD by my side is protection enough--the actual protection comes from me protecting my pup, not the other way around.
5. There is a lot of controversy over the correct way to discipline your dog, which I won't go into. I prefer positive reinforcement. Prevent the behavior from happening in the first place. If you don't, oftentimes a verbal correction is enough. Don't try to force your dog into doing a command he hasn't completely mastered yet. Also, down-stays are generally not corrections, they're just obedience commands in situations that call for it. At least that's my interpretation. Perhaps others can elaborate more thoroughly on correction techniques.
6. If you want to teach the "wait for treat" command, start out slow. Make him wait for 5 seconds, then gradually ramp it up to 10 seconds, then 30 seconds, then a minute, then a few minutes. You get the idea. If you start out big, he'll probably get frustrated and leave.
Sorry this is so long; I'm procrastinating from studying for an exam. Hope it helps!