Welcome to Subeta! Social groups here exist in several areas, one under 'Cults' (You can see the forum section under 'Subeta Features'), or Forum Groups (under Interact > Forums > Forum Groups on the top nav bar) - and a lot of people have special threads they like to talk in, so you can browse the forums that interest you and start talking with people - there are quite a few under Chit Chat in Small Talk in the forums too :)

Hope that helps a little, and don't be shy if you have any other questions!

Useful Links:

What to do on Subeta? Useful general information for newbies Finding friends (Chit Chat) SubetaLodge (Offsite item database, pet colours etc.)
FAQ