I agree that you really have to go and physically look at prospective breeders. Getting out to local dobe shows, (working as well as conformation) will help you in many ways, including possibly finding your new doberpup.
Having said that, you shouldn't cross breeders off of your list simply because they choose not to crop. There are many breeders who prefer the natural look of a dobe these days. It really is gaining in popularity. Also, there are some highly reputable breeders that I know of who only crop their show potential pups. However, they will usually offer excellent references to help you find the best vet in your area for cropping.
Definitely pay attention to what health testing is being done on breeding stock but, remember not all testing is predictive or a guarantee against future health issues.
Good luck in your search and research, lol.
