Here are some organizations and farms that make it really pleasurable for us to try to live and eat sustainably and locally in the Seattle area.
http://seattletilth.org/ - Their organic vegetable gardening intensive class and their class on raising chickens in urban environments are both awesome. They also hold great events, such as the Edible Plant Sale and the Harvest Fair. They will help you make composting a reality in your life.
Also, for composting, the City of Seattle will give you a great deal for certain types of backyard composters:
Puget Consumer Coop, your sustainable neighborhood grocery store: http://www.pccnaturalmarkets.com/
http://www.fullcirclefarm.com/ (great starting point if you have never been a part of a CSA before. They have a sort of CSA for beginners–they make it really easy to do)
Mushrooms, fiddleheads, sea beans and more: http://foragedandfoundedibles.com/
Excellent bread and grains: