I also have this fear. Just this past Wednesday I had to give the department report at our monthly staff meeting. It was less than 2 minutes long. I was fine, not nervous at all........right up until I started talking. Then I got super nervous and kept stumbling on my words. I talk super fast when I'm nervous. So I had to make an effort to speak slowly. I made it through (even though I flubbed my words a few times).
Now, I've worked for the same company for over 7 years. There are only 5 people here that have been here longer than me. I know everyone! I shouldn't be nervous. I am a talker, in social situations. But put me on the spot in front of people (and I didn't even have to stand up in the front, I sat in my chair) and I freak.

We had a Toastmasters group here before. I didn't attend, but several co-workers said it was a great thing and really helped them.