Fabric Depot, in Portland, has the largest supply of new fabrics I've seen anywhere. Their prices are a little below quilt store prices, but they have frequent sales with 35% off all fabric, and every month you get a coupon for a good savings on one item. In addition, in the summer they have an outdoor sale (under cover of course - this is, after all, Oregon) where you can typically get quality fabrics at $3-$4 per yard. I stock up during the summer and stop by occasionally during the big sales. They also have an excellent web site. Right now all their quilting fabric is 30% off.
http://fabricdepot.com/