Yes there are. Bridgetown hobbies, I believe on NE Sandy Blvd, Tammies Toy & Hobby is in Beaverton. I haven't been to Tammies in decades, but still hear it's a keeper for modelers. Bridgetown I never fail to go to when in Portland, it caters to modelers and wargamers.
There's a Hobby Town in Clackamas that's pretty good, it's really helps the car modelers with the AM and paint. I was there a few weeks ago to pick up some Spaz Stix paints.