Since I couldn't tell you about a yarn store in Quito today, I thought that I'd give you the skinny on one I found in Beirut.
Y.knot is a really great shop with a fantastic and friendly multi-lingual staff. They carry a wide variety of imported yarns such as Rowan and Anny Blatt. It is a beautiful shop, with a big rustic worktable and endless tea or coffee for sitting around knitting. I highly recommend it.
Mkhalissiya street 162
y.knot at cyberia dot net dot lb