We have an abundance of artisan sourdough bread being produced in the Seattle area. However, my personal favorite, Breadfarm in Edison, WA, is worth a trip up north. Some of my favorite flavors right now are the seasonal Allium Loaf and Sour Cherry Lemon. Super Yum!
You can find their bread at many natural foods stores and some groceries throughout Northwest Washington, but their retail store in Edison has a larger selection of breads and treats. Plus, they have a stand at several Farmers Markets, including Anacortes, Bellingham, Mt Vernon and (I just read this!!!) Everett. Everett has their market on Sundays starting in June, so if you are a Breadfarm lover, too, their bread just got a little closer to Seattle.