Ugh. I hate talking on the phone. The only way I've learned to deal with it is to take a deep breath, think about what I'm going to say (or write it down first so I can read it), and make the call, because the anxiety that builds up around making the call ruins my day, and is not often nearly as bad as the call itself. (Not to mention I look forward to the relief of having done it!). The sooner the better. The less time you have to think about it. There's also the possibility that you may get voicemail, when I am anxious, sometimes that is a relief.