I have been attending AA meetings for six months. I grew much more comfortable in the meeting room after about 3 months (reading the preamble, sharing, joking around with others, talking with others one on one). It is only now that I am starting to get into the more social aspects of AA - going out after meetings, friendship. I always had a hard time feeling a part of a group. I explained this to my sponsor and without hesitation he said "of course, that's why you were drinking."
From what I know about AA, volunteering does not necessarily involve giving speeches or leading meetings. We have people organizing barbeques & dances, driving people to meetings, making coffee etc.
Perhaps try and be patient with yourself. There are some really cool people in AA and you will grow into it naturally. At the end of our meetings, someone often says "I'm going for coffee, whose coming?" It's a good place to start.