For me it's as much about finding a community as it is about atheist activism. I highly value the community I got out of church growing up. I want my son to have the same sort of environment, without the dogma baggage.
Tell ya what, post an even here that you want to go to, and if my husband and I can join, we'll respond :) (He's Pitabred)
I'm a member of the meetup group but haven't ever gone to one of them. I'd like to check one out. I'll see if I can convince my wife to go to the breakfast. I'm not really interested in the book thing though.