Several editions of the official Kerr home canning recipe books can be obtained on eBay, Amazon.com, and Open Library. Open Library only allows borrowing the e-book copy.
Exact titles of the Kerr canning recipe books vary with the edition, but searching for "Kerr canning book" on these three sites should achieve results for multiple editions.
Amazon.com sells the editions ranging from the 1940s to 1990. Items are sold new and/or used. Most are priced in the $15 to $40 range, as of 2015. The most recent edition, published in 1990, is titled "Kerr Kitchen Cookbook: Home Canning and Freezing Guide."
Vintage Kerr canning handbooks, mostly from the 1940s, can often be found on eBay ranging from $5 to $20, as can additional home canning and freezing pamphlets in the $2 to $3 range.
Open Library has the 1990 edition, "Kerr Kitchen Cookbook: Home Canning and Freezing Guide," available as an e-book to borrow. An account with the site is required.