Try MoveOn PAC's "Adopt a Battleground State Precinct".
I'm working through MoveOn PAC's "Leave No Voter Behind." Focus is on likely Kerry supporters who are newly registered or have been infrequent voters -- in 10,000 "battleground precincts." We knock on doors and repeatedly pester people up through Nov 2.
Also, I just got word of this fun one: http://www.headcount.org/ .
(Oops, clearly I didn't read your post carefully enough, Ogged.)