I can't find the phone number of a dermatolgist I went to a few years
ago. He did a very simple procedure of removing some very small
brownspots on my face and neck.

I tried looking for his anme and number using the tel directory but no
luck.

I would like to get a list of the names of dermatologists in  that
city.  How do I go about it?
I tried getting phone numbers of American Board of Dermatology,
American Society of dermatology, etc. but they don't list their phone.