3; California (San Diego, Oakland and San Francisco) and Florida (Miami, Tampa Bay and Jacksonville).
Pennsylvania
http://en.wikipedia.org/wiki/List_of_current_National_Football_League_team_rosters Not limited to quarterbacks and not the most efficient thing around, but it'll get you there.
There are 3 quarterbacks
SEC
Tom Brady
Terrelle Pyror is a former Ohio State quarterback that is playing in the NF. Troy Smith and Joe Germaine are also former Ohio State quarterbacks that played in the NFL.
Sec
Tra Thomas
who are the 10 oldest quarterbacks in the nfl ?
acc
Eli Manning
Brett Favre, Joe montana, Terry Bradshaw, among others