If you're researching for a project, curious about the industry, or considering entering it yourself, you'll find this site helpfulu. A great cheat sheet with everything you need to know about the various fibers. A sleek, commercial site that serves as a fantastic starting point for any knitter. Knitting section host Alison Trembley-Boucher writes wonderful feature articles, and the site also includes live chats, discussion boards, and oodles of helpful links. The knitterly equivalent of National Geographic magazine, Interweave Knits is a fantastic all-around knitting publication.
Patterns are also first rate.
KnitReviews Holds a large collection of reader-generated book and pattern reviews. Don't miss her separate links page, one of the best I've seen. The Knitting Universe I consider this the Microsoft of the knitting world. Brought to you by the same folks who publish Knitter's Magazine and bring you the Stitches conferences, this site holds all sorts of stuff. Tips, tricks, books, patterns, and a community section.