Mystic Path to Cosmic Power plus 1500 Ways to Escape the Human Jungle by Vernon Howard
The Book of Unknowing by Peter Ralston
Intuitive Thinking As a Spiritual Path by Rudolf Steiner
Truth & Lie in an Extra-Moral Sense by Friederich Nietzsche
They're not meditation books but they have lots of good ideas that will provide the philosophical foundation to live your entire life in a meditative/contemplative fashion.
Also as far as becoming more "meditative" and calm through diet and exercise goes, you have to stop eating breads and all sugar-foods and high carb foods (most plants and fruits are useless unless they're fermented and even then not any kind of replacement for animal foods) and eat raw animal foods or you will not be physically healthy, period and being physically stressed will also stress out your mind. The human body produces about 30 raw eggs' worth of cholesterol every day for our brains to function when people for whatever reason don't eat it. You can save your body all that extra stress and work and energy just by eating high quality cholesterol in the form of pastured eggs, raw milk, etc. Start with Sashimi, Raw Milk, Raw Kefir and Raw Cheese and then move to other things if you can. The better the source (grass-fed/grass-finished/ Wild caught) the more nutrients you will get. Searing only about 20 seconds on each side is a way of eating meat about 80% raw. The ultimate "PsyOp" out there is the vegetarian agenda. As long as most "truthers" are leaning towards veganism and vegetarianism as the opposite end of the false dichotomy between factory-farmed garbage and vegetarianism and veganism, they will always be weak and full of anxiety and stress because they are physically deprived of nutrients and poisoning themselves. Vegetarianism only works as detoxing from standard processed food diets. But detoxing forever does not equal health and nutrition and your body will soon start cannibalizing itself for all the nutrients you don't give it, cannot possibly give it, even if you had access to every single plant in the world at the tip of your fingertips. Animals eat the plants, we eat the animals. That's how it goes. We are not what we eat, we are what we digest and we were certainly not made to digest plants.
Also check out the carnivore you tube channels such as Primal Edge Health