Doberman Rescue would be a great resource. If you need to rehome her, they would probably take her, but if you just need training, they can likely refer you to a good experienced person in your area.

http://www.dogsaver.org/doberman/ has a list of states that you can click for someone near you. "Doberman rescue" is not one specific organization, but it is a group of people across the country who have special expertise and love for this breed.