Bhante Gunaratana: Mindfulness in Plain English
Bhikkhu Bodhi: In the Buddha’s Words and Noble Eightfold Path
Christina Feldman: Woman Awake, Compassion, Way of Meditation, Soul Food, Silence, The Buddhist Path to Simplicity and Beginner’s Guide to Buddhist Meditation
Jack Kornfield: A Path with Heart
John Crook: World Crisis and Buddhist Humanism
John Teasdale: The Mindful Way Through Depression and Mindfulness-based Cognitive Therapy for Depression
Jon Kabat-Zinn: Wherever You Go, There You are: Mindfulness Meditation for Everyday Life and Full Catastrophe Living
Joseph Goldstein: The Experience of Insight and Insight Meditation Kit
Martine Batchelor: Meditation for Life, The Path of Compassion, Women in Korean Zen and Let Go: A Buddhist Guide to Breaking Free of Habits
Reb Anderson: Warm Smiles from Cold Mountains and Being Upright: Zen Meditation and the Bodhisattva Precepts
Sharon Salzberg: Lovingkindness: The Revolutionary Art of Happiness and Faith: Trusting Your Own Deepest Experience
Stephen Batchelor: Alone with Others, The Faith to Doubt, The Awakening of the West, Buddhism Without Beliefs, Living with the Devil, Confession of a Buddhist Atheist and Verses from the Center
Buddhanet ebooks has an extensive collection of Buddhist e-Books all free to download.
Access to Insight has many Buddhist texts and translations, free to download, and also lists of Buddhist organisations that offer free printed books and other resources.