dog that runs away

Question
I have a 9 month chocolate lab. I took her to puppy training and she did very well.The problems I am having is that if she manage's to get outside the house we can not get her to come when she is called.I tell her to stay,sit and I even lay on the ground and call her and nothing seems to work. We spent an hour trying to get her back but she just kept running and barking and at 10pm at night the neighbors didn't really appreciate that. I have tried getting her with treats,hell I even tried a 2" t-bone and that didn't work. I walk her every day up to 3 miles or I  take her to the park and run her. I don't take her leash off at the park when she is running because that is the only way I can catch her. So,I am kinda at a loss of what to try nexted. The other problem I am having is she is very agressive when someone comes to the door even if she knows them. I have to practically sit on her to get her to calm down. We have a glass door so she can see who is at the door. I take her out to public places so she can meet other people and she does fine so I don't know what her issues are. And last but not least,we have potty isssue's. We live in a 2 story house and when we are downstairs and she needs to go she will go to the back door and go directly to the spot she was trained to go. But if we are upstairs and she has to go she just goes. She knows where the back door is but she won't go downstairs to the door. So, I am not sure what to try nexetd.Thanks for your time.

Answer
As far as her running off, the best solution to that is to make sure that it doesn't happen.   I'm not sure if you have a fenced yard, but that could help a lot with getting some of her excercise needs.  If she is running out of the front door, you could try something called a scat mat.  It is something that will give her a little shock if she comes close to the door.  I don't usually recommend anything that will shock a dog, but it is much better than what could happen if she gets out and runs away or gets hit by a car.  Usually one or two shocks and stay away from the door.

As far as her housebreaking, I recommend using a crate when you can not supervise her in the house until she get her potty habits under control.  For recommended crating instructions, please see www.paw-rescue.org   On home page, under Robin's pet tips.   A dog is never too old to crate train.    
The crate could also help with her aggression when someone comes over.  You could put her in the crate and when she settles down, let her out.