tired of chasing my dog!!!!!

Question
I have a blockhead, red nosed, pit bull.  He is still a puppy (about one year and a couple months old).  He's not mean like most people think.  He is the sweetest natured dog, and he loves everyone.  My problem is that, every time someone opens the front door, he sneaks out and takes off running, (and believe me, he runs fast).  I'm so tired of chasing him down, plus I'm afraid that one of these times, he's going to get hit, (especially because I live on one of the busiest one way streets in town).  How can I train him, not only to come when he's called, but to stay inside the house, or away from the front door when it's opened.
                      PLEASE HELP ME!
                          I'M DESPERATE!
                             THANK YOU,
                                  Ashley

Answer
To train the dog to come when you call him is easy, get some treats and hide them in your pocket, call him first time while he is away and show him the treat, do that a couple of times, then start calling him with the treat in your pocket and give him a piece when he comes, after that call him while the treats are in your pocket and give him a smaller treat, untill he starts coming without treats.(Every time he comes praise him.)
To train your dog not to leave the house first you need to spay him. Next you need another person to help you train him. The person has to hide somewhere near the door where he can pop up and surprise the dog while hes leaving. you open the door and the moment the dog leaves the person has to jump infront of the dog surprising him and clapping his hands, call the dog back and he should come back. Do that a couple of times, keep changing the place of the person who hides, but it has to be next to the door.