All the above answer sounds much like my previous answers to this reoccuring question. I guess I should take it as a compliment. Happy to see anybody willing to learn. Of course, I leave medicating the dog as a last resort.
There are some other important things he didn't bother to copy. Take her out before stressful events, such as just before guests are due. Do not tower over her, and do not look her in the eye. Both are sign of dominance. On the other hand, obedience train her. Use more positive methods, with as little correction as posible. As she succeeds, and you are generous with praise, it will build her confidence and trust in her. You might do better working at home, than a class that she may find stressful. A good obedience book is about you being top dog, not about rewarding standard commands with a treat. Start at
http://www.dogsbestfriend.com/.
I often include this when I suggest tug of war. Ropes from the pets' store quickly turn to hazardous shreds. Ones I made lasted much better. Go to a hardware or home center that sells rope by the foot. Buy 2' of 3/4" poly rope. Melt the ends, and tie knots in it. Get them as tight as possible, put it in a vise and pound it with a hammer. Watch carefully, and be ready to discard when it comes apart.