New and experienced canners alike can be confused on the subject of gear. After all, newbies are new and the experienced among us can become hidebound by familiar methods. Home canning as we know it today hasn't been around so very long, after all, and it is just as influenced by science and technology as anything else. Methods change (witness new USDA recommendations for tomato processing times), as does fashion - you don't see much in the way of watermelon rind pickles these days but I get more hits for tomatilla salsa than anything else.
When someone asks me for recommendations for getting started with canning, I try to keep things simple and few in number. There are hacks and homespun ways to get around almost all of them, but I think that they're better accomplished by confident canners and do suggest that new enthusiasts stick to at least a minimal complement.
First: jars. I recommend Ball (or -type) canning jars. There are other varieties of jars but these are likely to be the most recognizable to those of us in the U.S. They are strong, will last for years with proper treatment (save a few losses here and there) and can also be used in the freezer. They take a two-part "dome" lid, the rings of which can be used over and over again (in fact, the you only need the rings to set the seal - once a jar is sealed you can take the ring off and store the jar without it, using the ring on the next jar to be processed).
For my money, the best canning kettle is one intended for canning. You can buy them with the rack included, and replacement racks are available. I've had my kettle for eight or nine years now and I'm ready to purchase a new rack. It is possible to use a spaghetti pot and wrap your jars in tea towels for cushioning but, even though I myself have done so (for quarter-pint jars) it's not the kind of thing that I think that newbies ought to do. If you already have a pot that will fit the rack dimensions, by all means spring for just the rack.
Then there are the little things, like a jar lifter, funnel, sterlizing rack, and magnetic lid lifter. Of all of these, I only bother with the jar lifter (although I often use folded towels instead) and funnel. The lifter is useful for righting tipped jars or fishing jars out of the kettle if the filled rack is too heavy to lift and a funnel is very good for filling jars without making a mess of the rims, which could interfere with the seal. A canning funnel is sized just right for Ball-type jars, too, and worth the expense in my opinion. The others...bah. Not worth it to me, but your mileage may vary. Once you have an idea of the kids of things you like to make, specialty stuff like cherry pitters and apple corers and food mills enter the picture. Hold off of these at the very beginning or borrow them unless you know for 100% certain you're going to want them and consume the products to which they contribute.
You can buy kits of various kinds that incorporate some or all of this gear. There are several online providers, as well, or you can check your old-timey hardware store. I routinely by lids at our locally-owned hardware place and I've been known to zip into the much-dreaded Wal-Mart in a pinch (although it seems to me that they are selling less in the way of reusable gear and more in the way of canning seasoning mixes). Several supermarkets in my area carry lids, rings and jars in their housewares aisles, too.
Like many hobbies, even practical ones, the start-up costs for canning aren't a trifle. I'm not sure I really save money through canning, although I'm pretty confident that I'm able to produce very high quality products for an excellent cost, not considering the intangibles of being able to deal with lots of homegrown or otherwise inexpensive produce. Since I use my jars for freezer storage, too, I think that helps me avoid food waste as well. Once people find out that you're canning, you will likely receive lots of jars - for some reason people have them in their basements a lot - and I've scored a few from Craig's List and FreeCycle. I buy lids all year 'round to avoid a large outlay in July through September - more of a psychological help than a real financial one.
If you're just starting out, it may be worth pitching in with friends for the gear and a few dozen jars and sharing the work of your first canning sessions. Sharing the work of chopping and boiling and mashing is a great way to learn and until you know if you'll be canning year 'round or wanting to produce a lot of your family's food in this way, you may as well go co-op on the equipment.
Next time, I'll make my website and book recommendations, and talk a bit about how to get one's hands on stuff to can.