Sorry for the ridiculous tardiness! family medical issues - I follow a range of people. 2 HS principals on twitter that I follow are @NMHS_Principal & @bhsprincipal. I also follow @simplek12 (just great tech resource); @shannonmiller, @cybraryman1 & @web20classroom - all great resources. There is a twitter chat - #edchat that is every Tuesday @ 7pm - its a great way to connect and network with peers
hope this helps - sorry again for the delay.
There's another Education Ning devoted solely to PLN's-- edupln.ning.com-- haven't looked in to all their networks, but it's a big site and I'm sure you would be able to get connected with some other great Language Arts teachers.