I go and quite enjoy them. At my meetings, and in the actual OA literature, we refer to our Higher Power (could be God, Allah, Buddha, flying spaghetti man, etc.). For me, and some of the members in our meetings, we sometimes refer to God as our higher power, for simplicity, but it is different for each person.
Meetings tend to be held at churches because rent tends to be free or very cheap.
I have found the meetings to be very open-minded and liberating. I can share things with them that I can't share with anyone else. Feel free to pm if you have any more questions.