I used to hate talking on the phone because I never knew how to fill awkward silences. There's no escape and you can't key off of body language or anything. And then my job forced (and still forces) me to use the phone as my primary means of contact with people. So what I did, at least for work and a bit for friends and family, is plan out how I would start the conversation and have a very definite purpose in mind.

My only problem is that I still don't like just chatting on the phone, unless I actually have something to say. Heh.