Zen
Master Hsu Yun's Discourses and Dharma Words, Edited and translated by Charles Luk
Zen Mind, Beginners Mind, by Shunryu Suzuki
Buddhism and Zen, by Nyogen Senzaki & Ruth Strout McCandless
Bankei Zen by Peter Haskel
The Way of Zen, by Alan Watts
The Tao of Zen by Ray Grigg
Upside Down Zen by Susan Murphy
Everyday Zen, by Charlotte Joko Beck
Zen Practice
Principles of Zen, by Martine Batchelor
Meditation Without Guru's (a guide to the heart of practice), by Clark Strand
Historical
The Shobogenzo by Dogen Zenji
Tranmission of the Lamp by Kaizan Jokin
The Zen Teaching of Master Lin-Chi,
The Sutra of Hui Neng, Grandmaster of Zen translated by Thomas Cleary
The Zen Teaching of Bodhidharma translated by Red Pine
Buddhism
Heart of the Buddha's Teaching, by Thich Nhat Hanh
Wisdom of the Buddha (The Unabridged Dhammapada), Translated by F. Max Muller
What the Buddha Taught, by Walpola Rahula
Other Works
Tao Te Ching by Lao Tzu
The Gospel of Thomas
Recommended Viewing:
Visual media which may be helpful to practice
Movies
Zen (2009 Japanese movie about the life of Dogen)
Enlightenment Guaranteed (German)
Avatar
The Last Samurai
The Matrix
Spring, Summer, Fall, Winter . . . and Spring (Korean)
Zen Noir
TV Series and Specials
Shogun (Original series with Richard Chamberlain)
Kung Fu (David Caradine, Keye Luke and Philip Ahn)