C.
Welcome to the area. I belong to a parents group called Parents Who Care (www.parentswhocare.org). It was a lifesaver when I had my first son.
It's run by volunteers who organize weekly playgroups and other activities. We host an Open Gym at the Hoffman Estates Park and Ice Arena (1645 W Higgins). It's every Monday from 10:30 to 11:45, costs only $1.50 per walking child and is open to the public. It's a great way to meet other moms and to let the kids run around, especially in the winter.
Hope this helps.
C.