Wool Works is a very comprehensive resource, particularly its list of knitting stores across the country. The site also features free patterns, knitting guild listings and more.
Borealis Sweaterscapes, in southern Maine, brings a higher level of artistry to intarsia knitting. They have patterns and kits for sale, as well as detailed tutorials on intarsia and information on key topics such as washing/storing your precious handmade sweaters, converting pullovers to cardigans, and print-your-own knitter’s graph paper. I adore their sock patterns & can’t wait to try the cow one.