Hi there,
I'm new to this site so pardon my 6 month late response! Great site, anyway, I'm an active member at tilth and the way to "hang out" the whole weekend with all the gardeners is to volunteer. When it comes time to get volunteers for the plant sale you can sign up for a volunteer shift and choose from a whole slough of jobs from helping people choose plants, to selling
compost, to just singing in other volunteers - there's a wide variety of jobs! It's quite fun, you hang out with hundreds of other gardeners aka volunteers, and there is always a post plant sale party in the green house afterwards. My first Tilth plant sale was much like yours and I've been volunteering ever since, the people are great and so is the gardening, it's really the best way to get involved.