This is a searchable online database of recording studios and mastering studios in the Pacific Northwest US and Canada, currently including Washington, Oregon, Idaho, Montana, British Columbia, Hawaii, and parts of CA and AZ. It may expand in the future (hey, any studios in Nevada? Alaska?), but for now the emphasis is on the NW area.
Note: You will need a version 4.0 browser or better, with "scripting" or "javascript" enabled, to use this site.