Home instead of nursery/preschool

My son is coming up to 3, and so far has not been to nursery, childminder, or anything like that. I just want to make sure he stays at the same level with his peers without, especially when it comes to socialising. Does anyone have any tips for this? We don't have a big family and I dont have friends with similar aged children. It's the main worry for me. We have always gone to stay and plays and music classes, though I'm not sure if he is now getting a little old for them.