Hi Becky. My son is now 8 months old but when he was 3 months I was ready to get out of the house and exercise and meet new moms just like you. I also put a request on this site asking the same as you. I got a response from a mom who teaches a fitness class at Demens Park next to the Pier. Her name is Christi and she teaches a class called StrollerFit... exercise with your baby. The first class is free, so I went and I was immediately hooked and signed up and have been going ever since. If you would like to see what this is all about you can visit the website at www.strollerfit.com or come join us one morning. We at 9 am in the parking lot on Mon, Wed, Thurs, and Fri... bring water, blanket, stroller and baby. It's a great workout and when we are done the babies and moms interact.
I am also a member of the Sweet P.E.A.S. mom's site that Abby sent you a message about. This is also a great way to meet other mom's.
Hope you find what you are looking for :o) -S.