I don't see an option to join social groups (specifically Region 8 but couldn't find others either). I joined a few a while ago, but don't remember how I did it and can't seem to figure it out this time.
If you look at the top of the page on the left under the words "chalk bucket" you will see the words "Forum" then "reviews" then "Social Groups" Just click on "Social Groups" and it will take you to the list of groups, but some are closed groups (no more members will be added) or by invitation only.
I have also run into problems; I can see the avatar of the mod, but no info beyond that - so I don't know who I should send a PM to. There is no name or mod info that I can find - which is weird because when I looked at it about a month ago it was obvious who the mods were. I'm confused.
Yeah, that's the problem. You don't see their name, you just see the avatar photo. If it's someone who posts frequently, you can kind of randomly find them on the boards, but if it's an unfamiliar photo you are really searching!