If you know how to get to the Capitol, parking shouldn't be a problem (a nice spot is in the church lot just accross from the front of the capitol building). Otherwise, there are lots adjacent to the building as well as some street parking.
In terms of getting freepers together...I'm not the most familiar with the area either but how would meeting at the bottom of the 'lowest' stairs (i.e. first steps next to/from the road) in front of the captiol between 11:45 and 12:15 sound?...