i guess you mean for therapy and not just the socializing?
i did a group for social anxiety - it costs money because it was run by two psychologist, but it was a bit helpful. we did CBT type work in the open and would set goals for ourselves and did exposure within the group (which was prob most helpful, since it was forced). i don't know how all of the groups work but i'd definitely recommend it to anyone who has the chance.
i'm also doing it again, but this time it is for a research study which is cool and since i'm a volunteer it is for free