Good selection of Cascade yarns.
Lettuce Knit is my favourite store in the city. Good selection of yarns that you might not find elsewhere - Socks that Rock, Blue Sky Alpacas, Fleece Artist/Handmaiden, Lorna's Laces. Friendly staff and they offer great classes too.
Check out their website for sales! Stocks Brown Sheep, Fleece Artist. Great selection of books and magazines.