Where do you buy your yarn?

[mamarudy]

Im looking for yarn to start my first pair of longies. While I'll likely opt for a more economically priced wool (like patons) for my first pair so as to account for mistakes, I am wondering where many of you find your yarn. It's already apparent to me that the selection at local craft stores is severely lacking. I know many here are big fans of mosaic moon, and I have to say after looking at some of her many colorways I can see why. It seems like co-ops are the main way of finding these, is that the case? Are there any other shops that sell yarns from say MM, DD, family roots(yes I know she has recently stopped dying), and others like them? I'm so lost as to where to find these