Mommy and Me groups?

Hi Ladies!

I am a 24 yr old single mom of a wonderful 8 week old.  I just got back into the swing of "real life" and being a working mom.  I am finding myself missing friends and friendships.  I am finding myself in the position of the only person who is a parent and I cant go out with all of them anymore.  I dont mind being home and spending time with my LO but I am looking for  a Mommy and Me group to join.  My trouble comes that I am not a stay at home mom, and the only groups I can find are geared aroudn that and they are held when I am at work M-F. 

My questions are these... Are any of you from Northern baltimore (or surrounding areas) that are part of a Mommy and Me for Working moms like on the weekends or one of the week nights? and if not Would any of you be interested if I got one started maybe a fitness group at a gym? or one to organize these groups to get together and walk, or have coffee, or something of the sort to meet other moms with babies/infants/toddlers?

Thanks!!!