I would have to recommend any book by Dr. John McDougall (the New McDougall Diet, McDougall Program for Maximum Weight Loss), Dr. Joel Fuhrman (Eat to Live), or Neal Bernard. I would also highly recommend reading T. Colin Campbell's The China Study - you will never look at our Western diet the same ever again!
I agree with all of these. I am currently reading the McDougall Program for Maximum Weight Loss. I read Dr. Furman's End to Diabetes and completely reversed my diabetes with it. Excellent resources.
The Omnivore's Dilemma by Michael Pollan. Although its not so much of a how-to for eating healthy foods, but an investigation of the entire food industry, from small organic farms to "industrial organic" to conventional food industry.
The Whole Foods Diet: The Lifesaving Plan for Health and Longevity
I personally would suggest 'The Whole Foods Diet: The Lifesaving Plan for Health and Longevity' by John Mackey . It has been the best seller of its times and has pushed the readers to understand the significance of food and diet in today's busy stressful lives. I personally am not so big fan of reading books but you can obviously listen to the books which stresses upon serious topics and motivates us