I've had limited success in finding delicious doctors. Well, I might have found some and I don't know. I have certainly come across a few people who are very good at tagging sites relevant to me. But it is a little bit frustrating that I can not get in contact with these people, who are interested in the same things as me, to find out who they are and what they do. They might even be part of the elusive medical education community!
There is no way to directly contact another user in delicious if they do not have a website or email address listed. So I have to resort to other methods to make contact. I can join them to my network, send them a link and add a hello message to the note I tag, but I can't just send them a message.
Maybe there are good reasons for this. Maybe it prevents spam. But maybe it is just because delicious don't think it is very relevant. On their help page they state that your network might consist of "even new people you run across while exploring Delicious" so it doesn't seem to be considered a primary purpose of the site. Anyway, I have contacted them to find out and will let you know. I'll also tell you if anyone has responded to my strange hello notes!