Events are already scheduled in Boston, Chicago, San Francisco, and NYC. You can register your own local event by sending mail to protest@saveaccess.org.
If anybody's planning to go to the San Francisco protest at "AT&T's main San Francisco headquarters at 666 Folsom St.", they'll be disappointed or confused. That building's been closed long enough that they've taken the Credit Union ATM machine away from the front entrance :-) (This is frustrating, because it means that the nearest one is now about 8 blocks away from my SF office instead of 1 block.) There are three or four other AT&T / SBC buildings near there, one of which has a nice big plaza and few windows, and another of which had a Cypherpunks meeting there once in the 90s. I'm unlikely to attend - I've got things to do down in the south bay. And unfortunately, IMHO their accuracy on other issues is about on par with their directions. They've got the Ballpark right, but it's big enough that it's hard to miss, and our corporate leaders do need yelling at for being boneheads, but they don't appear to understand the technical issues with network neutrality.