The best tips I can give you are:
1) Research thoroughly the breeders and go to a reputable one who health tests and does all the other responsible things. (learn about all the genetic diseases they can get) You can find online what makes a responsible breeder. You can go to shows and talk to people. If one or two breeders names keep popping up, you might look at them.
2) Have you ever had a dog before? These are not dogs for beginners. They are a lot of dog and can be a challenge.
3) I'm so glad you've been reading a lot. Thats so important and wise. Be sure to learn a lot about training and be prepared to do a lot of it and to do a lot of exercise yourself. That's what they need tons of as they mature, as well as a mental job.
I wish you the best. Just be sure it's the right breed for you and your activity level. A lot of people get them for the wrong reasons and then find out they don't like them after all because they're very, very busy and they never seem to slow down, don't let anything go by them. They have to have their noses into everything. LOL.
They are definitely not a dog for everyone.
I think there are some stories sprinkled around this forum. There's something I wrote... a little story about mine in this forum...thread called,
Is this multiple personality disorder? (LOL).
Here's a link also to a Doberman forum:
http://www.network54.com/Forum/11341?it=0
(I hope that's ok to do this here. Those people there are pretty helpful where Dobermans are concerned.)
Plus, there's a ton of stuff online in the AKC and DPCA sites. Good luck.