http://www.homecanning.com/usa/That's the website for the Kerr/Ball company (makers of canning jars and related supplies like pectin). If you think you're going to do this somewhat regularly, I strongly encourage you to buy their $4.95 book on canning basics (they haven't changed the price on this gem since I bought my copy over 15 years ago!). Here's the link to buy the book:
http://www.homecanning.com/usa/ALOrder.asp?P=2576Amazon.com has tons of other books on canning, but you can't beat this one for a basic primer.
The website will give you the basics. For acidic foods like tomatoes, fruits and pickled foods, water-bath processing is all that's required, and it's easy to do (and all you need is a BIG pot, and usually a rack that sits inside the pot to place the jars on). If you want to can low-acid foods like corn or green beans, that requires processing in a pressure cooker. I've been canning for several years, and I'm only just now comfortable with the idea of playing around with one of those (and I'm hardly shy about trying new and challenging kitchen jobs!).
It can be addicting, but more important--it's a great skill to have. Should our oil woes begin to impact things like transportation of the country's food supply, you'll know how to grow and preserve enough to get you by.