First question: do you have medical insurance? And if so whom?

Most insurance companies will want you to use their doctors, so that will limit your choices (unless you want to pay a lot). This is very true of Kaiser.

Most psychiatrist and psychologist can treat ADD/ADHD but few are specialists in it and even fewer specialize in treating adults.

Whoever you do end up seeing, send time asking about their experience treating ADD and how they deal with difficult cases (speaking from experience as one who can't take most medicines).