This started as an email to a friend who asked for some getting-started advice. I've had so much fun thinking about this that I thought it might make a decent blog post as well. Please add your own advice in the comments--she'll be reading this! ;)
First, it helps to know your learning style. Some do well with written instruction; others need images. Some can manage with static resources (books, videos) while others need direct feedback (forums, IRL knitting groups). You'll have a lot of questions as you start, and knowing how to ask them is going to get you the most useful answers. That said, here are some of the resources that I've found useful for learning:
Ravelry. Get thee to Ravelry. Immediately. It's free to join and it's THE online spot for all things knitterly. The best part for beginners? Forums, forums, and more forums. Thousands. Yes, THOUSANDS, of other knitters from whom to ask advice. And do not get me started on the searchable pattern library. My queue is unrealistically long.
Knittinghelp.com This site has a number of tutorials for basic techniques, and special tricks. Many have images. Many more have short demonstration videos. And the folks who run it were nice enough to produce many of the videos with versions for English and Continental styles, so you can get the best advice for how your hands work. (A quick note on styles; don't let anyone fool you. Neither is superior. Do what feels most comfortable to you. My own style is kind of a mash-up. Pickers, throwers...we all get it done.)
Stitch and Bitch. Yeah, I know. But the teaching style in these books is very chatty (appealing to me) and easy to understand, and the projects are easy enough to get your confidence level up and trendy enough to actually look like something you might actually want to wear/use. You may grow beyond it, but it's a good place to start.
Knitty I adore this online knitting magazine, and not just for the always-anticipated quarterly publishing of gorgeous free patterns. It has a wealth of instructional articles, all searchable in archives.
And once you get into the swing of things, you'll likely seek out specific advice. Many people swear by Elizabeth Zimmerman (books). I love Wendy Johnson and Cat Bordhi for help on socks. But I'm getting ahead of myself.
Next step is to find a project. I am the absolute worst person to ask for advice on this. I taught myself to knit and purl using a LeisureArts pamphlet, made one wonky ribbed hat, and immediately dove into a textured baby blanket. I reinvented the wheel on a few things (like stitch markers), and made a TON of really stupid mistakes simply because I wasn't yet familiar enough with things to realize when I was goofing up. Of course, the baby blanket was for my first child and between the "love in every stitch" and the nostalgia of my naive optimism as I worked on it, it's probably my favorite piece. Warts and all.
Well? Maybe that's not a bad thing, then. But if you're the kind of person who is easily frustrated, or Type A, or who just wants something that actually looks nice when you're done, you'll do best to start with an easy project. A simple scarf in either garter or stockinette stitch is useful, lovely, and builds "muscle memory" for the basic stitches. Your first sweater should probably be a pullover with drop shoulders. Simple shapes, simple stitches, simple construction. I refer you back to the Stitch and Bitch books for some easy learning projects.
Finally, the stuff. This is a tough one. I find it hard to recommend really high-end materials to someone who may or may not keep up with the craft. On the other hand, using low-grade materials can lead to frustration and less than satisfactory results. I'll try to find a nice middle ground.
So, you need to buy some yarn and needles. At some point, you will want to seek out a LYS, or Local Yarn Store. KnitMap will help you locate shops by zip code. A LYS is a wonderful place to touch and feel yarn before purchasing (I've had good luck buying online, but have also had a few nasty surprises). They are usually staffed by knowledgeable and friendly people who should be able to help you with anything from selecting products to working out problems. And most of them host knitting groups, or knit nights, where you can go for a casual meeting and meet other people who enjoy the craft.
I'm frugal and shy (yeah, as chatty as I am, you wouldn't think, right?), so if I were taking you shopping for the first time, I'd probably just go to a chain craft store.
Horrible, I know.
Now here is where you enter a minefield. You *can* get some halfway decent stuff at a chain store. But you can also get some real junk. My recommendation is to get a yarn that is either 100% wool (if you are okay with hand-washing), or a wool blend (typically washing-machine safe). I know it sounds snobby to be anti-acrylic, and there is a range of quality among the acrylic brands, but the more experience I have with them, the more I'm convinced that they are just evil. Patons Classic Wool? Not bad. Lion Wool-Ease? It'll do. Cotton-Ease? Quite nice, actually. Red Heart? Step away from the yarn bins.
Seriously. Don't let the variety of colors fool you. Red Heart is the work of the devil. Yes, this means that you will not be doing your yarn shopping at Wal-Mart, so scratch that idea from your mind Right. Now.
If you do go to a yarn-centric boutique, LYS, or shop online (which I don't do enough to have an opinion, but several friends love KnitPicks for selection, price, and shipping), look for Cascade 220. It's available in an obnoxiously large palette of colors, is inexpensive (my favorite LYS sells it for $6 a skein, comparable to what Lion products go for at the chains--and it's a far superior product), and is a dream to work with. It is soft and durable. It's low-pilling while you're working with it but felts very well if that's your thing. I could say more things about how much I love it, but we'd be here all night.
And this post is already getting out of control for length. Sigh.
Finally, you'll need some needles. If you decide to commit to being A Knitter, you will want a full set of sizes, in a variety of materials. For just-starting-out, I would actually advise getting a basic pair of aluminum needles. Why aluminum when the bamboo are so darn nice? Well, the bamboo (and other wood) needles are indeed nice--for many yarns. But not for all of them. If your chosen yarn is "toothy", or if you knit tightly (a common problem amongst beginners), wood needles can actually make things more difficult for you. Most yarns will slide nicely over the metal surface. You can go fancy later.
I would start out with needles in a size 6 or 8, and I suggest making one of your first sets a circular needle. NO, I do not think you should start circular knitting until you are more comfortable. However, a circular needle (two short needles connected by a long cable) allows you to knit flat projects without holding the entire weight of the piece on the needles the entire time (lovely for baby blankets and sweaters). Short needles are also much easier to use; you're not banging them into your lap or the tabletop or whatever. Later, when you do decide to try knitting a tube...well, you'll already have a set of circulars. And I am *all* about items that are versatile.
What else? Really not much at the beginning. You may benefit from a set of stitch markers, but you can just as easily use small hair bands or a scrap of contrasting yarn, so that's not a necessary expense. If and when you decide to do a larger project in which you'll need to count rows, you could keep a scratch paper with hash marks (my old method), or you could go visit the nice ladies over at CrimsonOrchid Designs, who sell the most beautiful row counter bracelets. I think I have four of them now, and I love them dearly.
Knitting is one of those things that you have to DO before you really know what to ASK. My best advice is just to go slowly and try not to get overwhelmed. You'll be surprised how quickly you go from struggling to read a pattern, to modifying patterns. And then designing them...or going completely free-form.
Congratulations for deciding to try this! It's a soothing hobby, meditative in the repetition, challenging in the details, and rewarding in the final tangible product. Oh, and it's portable, which I can't say for my beloved sewing machine! LOL Good luck to you. <3