Here are some outside links for information about canning and food preservation:
Websites:
National Center for Home Food Preservation
Iowa Extension – Canning Tomatoes
Oregon State University Extension – Food Preservation
Purdue University – Complete Guide to Home Canning
Find a “Pick Your Own” place by you
Books:
Ball Complete Book of Home Preserving
The Complete Book of Small-Batch Preserving
The Everything Canning & Preserving Book
Stocking Up: The Third Edition of America’s Classic Preserving Guide