Sew-sisters.ca is very good. I have used their on line store and have visited their brick and mortar store in Toronto. There are a couple of good stores in the US that do not charge an arm and a leg to ship here. Connecting Threads and Fabric.com come to mind. Depending on the amount that you want (and the kind of sale price you might get) I have found that a large order is often better than a couple of small ones.