West Seattle Amateur Radio Club 
http://www.westseattlearc.com

Seattle Auxiliary Communications Service (ACS)
http://seattleacs.com/
http://seattleacs.wordpress.com/  (Seattle ACS Blog)

Amateur Radio Emergency Service & Radio Amateur Civil Emergency Service (ARES/RACES)
http://www.aresofkingcounty.org/

Communication Academy
http://www.commacademy.org/

The Seattle Channel
http://seattlechannel.org

Seattle Community Network, "Neighborhoods on the Net"
http://www.cityofseattle.net/neighborhoods/net/

List of Seattle-area & regional media
http://www.seattle.gov/html/citizen/media.htm