Sit Happens... they have a website
http://www.sithappens.org, you can take your puppy to "puppy playtime" until they are 5 months of age...
Apparently the period of socialization of puppies is until they are 20 weeks old, so as many positive experiences before that is a good thing for a happy dog...
Our 5 month old pup went to about 6 of the playtimes and 3 of their "bright puppy" classes, it was a good experience for him, and now he's going through the training up there as well...