Here are the three basic books I recommend to those who have a good foundation in the Four Noble Truths and the Eightfold Path:

• "The Threefold Lotus Sutra"
  - translated by Bunno Kato, Yoshiro Tamura, and Kojiro Miyasaka.
  Kosei Publishing Co. Tokyo
  ISBN 4-333-01630-4
  
• "Shapers of Japanese Buddhism"
  - edited by Yusen Kashiwahara and Koyu Sonoda.
  Kosei Publishing Co. Tokyo
  ISBN 4-333-01630-4
  
• "Stopping and Seeing: A Comprehensive course in Buddhist Meditation"
  - by Chih-i, translated by Thomas Cleary.
  Kosei Publishing Co. Tokyo
  ISBN 1-57062-275-2
  

• "The Four Noble Truths"
  - by the Dalai Lama
  Thorsons 1997
  ISBN 0-7225-3550-3
  
• "The Teaching of Buddha"
  - Bukkyo Dendo Kyokai
  ISBN 4-89237-251-x
  
• "The Way to Buddhahood: Instructions from a Modern Chinese Master"
  - by the Venerable Yin-shun.
  Wisdom Publications 1998
  ISBN 0-86171-135-5
  
• "Buddha of Infinite Light"
  - by D.T. Suzuki.
  Shambhala 1998
  ISBN 1-57062-301-5
  
• "Foundations of T'ien-T'ai Philosophy"
  - by Paul L. Swanson.
  Asian Humanities Press 1989
  ISBN 0-89581-919-8
  
• "Dhammapada: The Sayings of Buddha"
  - Rendered by Thomas Byrom.
  Shambhala 1993
  ISBN 0-87773-966-8
  
• "The Book of Buddhas: Ritual Symbolism on Buddhist Statuary and Ritual Objects"
  - by Eva Rudy Jansen
  published by Binkey Kok
  ISBN 90-74597-02-5
  
• "The Heart of the Buddha's Teaching: Transforming Suffering into Peace, Joy, and Liberation"
  - by Thoch Nhat Hahn
  Parallax Press1998
  ISBN 0-938077-81-3
  
• "Entering the Stream: An Introduction to the Buddha and His Teachings"
  - edited by Samuel Bercholz and Sherab Chodzin Kohn.
  Shambhala 1993
  ISBN 0-87773-981-1
  
• "Zen-Shin Talks"
  - by Sensei Ogui.
  Zen Shin Buddhist Publications 1998
  ISBN 0-9658352-1-9
  
• "The Lion's Roar: An Introduction to Tantra"
  - by Chogyam Trungpa.
  Asian Humanities Press 1989
  ISBN 0-87773-654-5
  
• "Zen for Americans: Including the Sutra of Forty-Two Chapters"
  - by Soyen Shaku/translated by D.T. Suzuki.
  Barnes and Noble 1993
  ISBN 0-88029-206-7
  
• "Zen Buddhism: A History Volume One India and China"
  - by Heinrich Dumoulin
  MacMillan 1994
  ISBN 0-02-897109-4
  
• "Zen Buddhism: A History Volume Two Japan"
  - by Heinrich Dumoulin
  MacMillan 1993
  ISBN 0-02-908240-4
  
• "Zen Buddhism in the 20th. Century"
  - by Heinrich Dumoulin.
  Weatherhill 1992
  ISBN 0-8348-0247-3
  
• "Thousand Peaks: Korean Zen-Tradition and Teachers"
  - by Mu Soeng.
  Primary Point Press 1991
  ISBN 0-942795-02-4
  
• "How the Swans Came to the Lake: A Narrative History of Buddhism in America"
  - by Rick Fields.
  Shambhala 1992
  ISBN 0-97773-631-6
  
• "The Path of Compassion: Writings on Socially Engaged Buddhism"
  - edited by Fred Eppdteiner.
  Parallax Press 1988
  ISBN 0-938077-02-3
  
• "The Way of the Bodhisattva"
  - by Shantideva/translated by the Padmakara Translation Group
  Shambhala 1997
  ISBN 1-57062-253-1
  
• "Bodhisattva of Compassion: The Mystical Tradition of Kuan Yin"
  - by John Blofeld
  Shambhala 1988
  ISBN 0-87773-126-8
  
• "Only a Great Rain: A Guide to Chinese Buddhist Meditation"
  - by Master Hsing Yun.
  Wisdom Publications 1999
  ISBN 0-86171-148-3
  
• "The Path is the Goal: A Basic Handbook of Buddhist Meditation"
  - by Chogyam Trungpa.
  Shambhala 1995
  ISBN 0-87773-980-6
  
• "The Miracle of Mindfulness: A Manual on Meditation"
  - by Thich Nhat Hahn.
  Revised Edition by Beacon Press 1987
  ISBN 0-8070-1201-7
  
• "The Buddha in Daily Life: An Introduction to the Buddhism of Nichiren Daishonin"
  - by Richard Causton.
  Rider 1995
  ISBN 0-7126-7456-x
  

• "The Door of Liberation: Essential Teachings of the Tibetan Buddhist Tradition"
  - by Geshe Wangyal.
  Wisdom Publications 1995
  ISBN 0-86171-032-0
  
• "The Heart of Awareness: A translation of the Ashtavakra Gita"
  - by Thomas Byron.
  Shambhala 2001
  ISBN 1-57062-897-1
  
• "Visible Here and Now: The Buddha's Teachings on the Rewards of spiritual Practice"
  - by Ayya Khema
  Shambhala 2001
  ISBN 1-57062-492-5
  
• "The Large Sutra on Perfect Wisdom: With Divisons of the Abhisamayalankara"
  - translated by Edward Conze
  University of California Press 1975
  ISBN 0-520-05321-4
  

• "The Flower Ornament Scripture: A Translation of the Avatamsaka Sutra"
  - by Thomas Cleary
  Shambhala 1993
  ISBN 0-8773-940-4
  
• "Complete Enlightenment: Zen comments on the Sutra of Complete Enlightenment"
  - by Ch'an Master Sheng-yen
  (contains the entire sutra as well)
  Shambhala 1999
  ISBN 1-57062-400-3
  
• "The Diamond Sutra and the Sutra of Hui-neng"
  - translated by A.F. Price and Wong Mou-lam.
  Ryukoku University 1984
  ISBN (not available)
  
• "Buddha-Bahsita-Amitayur Dhayana Sutra"
  - by Kalyasas.
  American Buddhist Academy Press
  ISBN (not available)
  
• "Buddha Tells of the Infinite: Amida Kyo"
  - American Buddhist Academy 1973
  ISBN (not available)
  
• "The Awakening of Faith"
  - by Ashvagosha translated by Timothy Richard D.D..
  University Books
  ISBN (not available)
  
• "The Light of Wisdom"
  - Root Text by Padmasambhava
  Commentary by Jamgon Kogtrul the Great
  Shambhala 1995
  ISBN 0-87773-566-2
  
• "Elegant Sayings"
  - by Nagarjuna and Sakya Pandit
  Dharma Publishing 1977
  ISBN 0-913546-13-5
  
• "Buddhist Texts Through the Ages"
  - edited by Edward Conze, L.B. Horner, David Snellgrove, and Arthur Waley.
  Harper Torchbooks
  ISBN (not available)
  
• "A Complete and Detailed Exposition on the True Buddha Tantric Dharma"
  - by Master Sheng-yen Lu.
  Purple Lotus Society 1995
  ISBN 1-881493-04-0