In the best interests of all and to save a discussion on which Dr.'s in that area are better, I will spare you my opinions and research on the issue.
However, I must tell you to do plenty of research and talk to previous patient's if possible. I know you dont want to hear this, but 21 is young for a hair transplant. While I am not saying that it is too young (it depends on the case, of course) you are most certainly going to have more loss after the hair transplant. Make sure you find a physician that will accomodate his plans for you on a long-term goal basis.