For free! Amazon, along with others, like Project Gutenberg and the National Archives, have many of the old books on gardening and plant life, in e-book form for e-readers. I even found a book by Steve Soloman, the author of Growing Vegetables West of the Cascades! His book available on Amazon for free is Organic Gardener’s Composting. It is also available as a paperback, but not for free. There are a great number of old free gardening books available online. They may not be the how-to type, but they will give you a sense of life before plastic, internet and the chemical fertilizers so many have come to use so regularly.
If anything, they will accompany some time while you’re waiting for your lettuce to grow!