I recently went to a new place in Staten Island called the Yarn Girl. It just opened in May and I believe it's one of few places in Staten Island. The store has a great collection of yarns and it's a bright, clean, and airy place.
It's located at 851 Castleton Avenue, Staten Island, Tel. 718-447-6117. Right now they are only offering knitting classes. It was certainly worth the trip there.