Welcome to PDX! Great city with plenty of games going on.
You can find some information on the Portland Rounders venue here:
http://www.portlandrounders.com, and for the groups that play there on Monday through Wednesday you can find more details (and invites) here:
http://poker.meetup.com/127/
Last I heard the Friday games (which are quite good) were closed to "drop-ins" - so you need to come with a member to get into those. That may have changed, but I doubt it. The Meetup games are still open, although you may need to join the email list. I occasionally play in these games and the skill level is all over the board. There are definitely some strong players on Friday nights where the buy-in is typically higher, but there are still many with less skill (including myself). Generally the tournout is good with anywhere from 4 to 6 full tables per night.
There are also plenty of home games of various stakes around and once you start chatting with folk you will certainly get more detail on those.