K.D.
Hi I know there are a few at http://www.playgroupsusa.com/
It's free to join and easy to navigate.
If you're looking to just find other moms to have playdates with I'm in Troy. I have a almost 4yo boy, a 2yo girl and a 6 month old baby girl and we are always up for making new friends and getting out of the house.
Please feel free to PM me if you'd like to know more.
K.