I'm pretty much the exact same as you. The planned officials phone call thing is actually crippling my life. I'm also really bad with acting where I have to memorize lines or read aloud, but spontaneously - even public speaking - I can be quite amazing. I've been practicing reading out loud using free classics on Google Books. While I haven't done it too long to see results socially, what I can say is that talking *slowly* helps. What I have to work on next is my social anxiety and basically the fear of myself stuttering.  Don't know if this helps.