I'm glad you bumped this thread. Two great things about Seattle that previous posters missed:
1) The Stumbling Monk - an unpretentious beer lover's bar in Capitol Hill.
2) 90.3 KEXP FM - a truly original indie radio station for many reasons. They have live streaming of their broadcast at
www.kexp.org and you can also listen to any music from the last 2 weeks. They play a lot of new music and many now-famous bands got their big break on KEXP.
I will add that KEXP plays music diverse enough that some shows/music are bound to turn you off, so you can't just listen to the first song that happens to be playing and decide if you'll like the station or not (which is something you CAN do with most stations). Take that for what it is worth.