Ravelry is the best place to find patterns and yarns, discuss them with other knitters, and make knitting friends. It is really a remarkable site, and I believe the wait list is down to a couple of days now.
Garnstudio in Norway publishes DROPS patterns, hundreds of them, for FREE on their site, garnstudio.com. They bring out new collections every season, and their printed pattern books are also available for a couple of dollars.
Nordic Mart sells all Garnstudio yarns. They make a lovely, reasonably priced Alpaca.
Elann has a wide selection of their own brand yarn, and also some closeouts of other brands. Their shipping is expensive (they are a Canadian company), but the yarn prices are very low. I love their Baby Silk and Baby Cashmere blends.
Knit Picks is a great company that sells their own reasonably priced brand of yarn plus needles and patterns. Their interchangeable circular needles will change your life.
Yarnzilla sells lots of gorgeous luxury yarn, and is the place to go for a splurge. They have good sales, too.
Webs has a vast selection of yarn. Awesome sales, and they give a volume discount.
Knitty is an online knitting magazine that has free patterns every season and some interesting articles.