Dan, I went to my first AA meeting earlier today and I was exactly the same as you - dreading it. It only took about 2 minutes after I walked through the door before I started to relax. A really nice bloke started talking to me about football which distracted me and in a way it felt like I was stood at the bar chatting to a random stranger.
Once the meeting started I relaxed even more as I realised everyone was focused on the person talking. No-one looked at me, I didn't have to speak, all I had to do was sit and listen. I got so engrossed in what people were saying I forgot I was even at AA until the end.
I hope this helps. I put off going for years because of the fear but now I've cracked it I'll definitely be going back. I feel like I've got 2 new mates that I didn't have at the start of the day and I'm not one to normally socialise or speak to strangers (without a beer of course). I'm looking forward to getting to know more of the people there.