Not familiar with Seattle's quilt shops, but if you have access to a car you might consider taking the ferry to the Kitsap Peninsula. There is a wonderful quilt shop in Kingston, where one ferry docks, then a few miles from there is Quilted Strait in Port Gamble, which is one of my favorite quilt shops. There is also a nice shop in Poulsbo and Material Girls in Silverdale. That would make a nice day trip from Seattle.