Fellow AP'er here. I do have an AP playgroup but it's for little ones (our kiddos were born in March, April, May). You might try www.birthcarenetwork.com. They have a new mothers' group that meets every month or so--I know you're not a new mom, but some of those ladies may have some information for you that will help you find some playmates for your older child. I *think* they are meeting at the Louisville Zoo tomorrow, I could be wrong. Laura Holt used to be in charge of that group--her e mail is on the "referral" page, she's a certified doula.
Good luck...there are plenty of AP mamas around here...I just got lucky that me & all of my crunchy friends got pg at once.
If you are still bf-ing, you might want to join your local LLL group. I know that our group has a regular meeting once a month, as well as a toddler meeting once a month. A bunch of those moms get together once a week for a playgroup.
Welcome to Louisville! I've just started going to a new AP playgroup, I think they've gotten together 3 or 4 times. There are a couple of 2 year olds (my dd is one of them), a fourteen month old, an eight month old, and then a lot of babies between 3 and 6 months.