The books I used are decades old (and reviewers don't seem to like the updates). But here's one I've heard newbies say they like (Organic Gardening For Dummies) http://amzn.to/1bCR8rj Just start there, and keep going.
There are enough organic-growing systems, ideas, and techniques to make your head spin and spin and spin, von. As you plant, observe, harvest, and (hopefully) eat, you'll naturally gravitate to various other sources of info.
Everything feels fragmented and narrow at first. Why? Because you have to do things (learning on the job) in some sort of sequence, one small, painful step at a time, while in the natural world, everything's connected to everything. (Popular culture doesn't begin to make it clear just how much skill & knowledge it takes to produce a good cabbage.)
Don't get too perturbed over flubs and failures. You're gonna make a lot of mistakes. Start small and build on your successes. Grow only what you like to eat. Spend a LOT of time just observing what's going on in your garden. Pick up leaves and check what's going on underneath. Lift that cardboard mulch and delight in the extraordinary community of organisms you find there. Wonder a lot.
Find a few veteran gardeners you can call on for help. Nothing beats the global tribe of home food producers. They can help you choose suitable varieties for your needs and locale, understand how to sow and transplant, irrigate, fertilize, identify insect pests and diseases, and more.
P.S. Heirloom seeds? Often a great choice. But please don't turn up your nose at hybrids and open-pollinated varieties from modern plant breeders. Many of them confer important disease or insect resistance, tolerate adverse conditions better, offer cultural advantages (compact growth habit, easier to harvest) and other benefits too numerous to list.