Garden Food Preservation and Safety

Last August, the 16th to be exact, my dear Godmother Auntie Clara and Uncle Nick gave Shermen and I a pressure cooker for a wedding gift. It was so appreciated, especially considering I'd started home preservation in 2006 by canning pickles in a water bath using a camp stove. The camp stove / water bath combination really limited what i could safely preserve via canning to pickles or the highly acidic tomatoes. Everything else was blanched and frozen, (taking up huge amounts of freezer space.) One of our frozen favorites was a stewed up batch of tomatoes sauteed with herbs, garlic, onions and eggplant. Even after freezing and reheating, it tasted like summer.
Last fall I was so excited to recreate the recipe, only preserving by canning rather than freezing. My new pressure cooker allowing me to can the non-acidic veggies without worries. However, this winter when we opened a jar of "stewed tom w/eggplant," the smell was just off. The jar was properly sealed, but the fear of botulism caused us to turn to a jar of Prego instead.
Yesterday, there was a great program on Wisconsin Public Radio with Larry Meiller about gardening and food safety. There you can find a link to listen to the actual program. Besides food safety, they all discussed state laws when it comes to setting up "road side stands" to sell produce, and what you actually can sell at produce stands in terms of enhanced, or preserved, produce. I found this particularly interesting because living in a tourism area, I have considered selling preserved items for tourists to take home as gifts / momentos, but wondered about legal issues. Think I'll be waiting a few years on all that.
The website FOODSAFETY.WISC.EDU has tons of information also.