I've only done a little bit of canning, but I'm with Sue about finding good used stuff. If you go for all new stuff the costs will mount quickly, especially those new fandangoed pressure canners. Good quality used gear is perfectly fine. Watch that gasket though. As Sue points out, it's crucial if you use a pressure cooker,

My Grandparents had a huge subsistence garden, and canned and froze whatever was in season. Our garden is pretty pathetic in comparison so we buy most of what we can. We're usually lucky enough to have neighbours and friends share their bumper crops. The cost can add up quickly at the grocery store so buy in-season. Around here, local produce is more expensive than going to the grocery store, but I like supporting the local farmers. Thanfully, we're set-up to do smaller batches so we can do a bit at a time.