Buddhism

    Buddha (Penguin Lives)
   by Karen Armstrong

A biography of Buddha with an exposition of Buddha's teachings in a brief book

    Change Your Mind : A Practical Guide to Buddhist Meditation
   by Paramananda (Paperback - January 1996)

The simple, no non sense guide to Buddhist meditation

Insight Meditation : The Practice of Freedom (Shambhala Dragon Editions) -- by Joseph Goldstein; Paperback
  A very readable account of Theravada Buddhism

The Experience of Insight : A Simple and Direct Guide to Buddhist Meditation -- by Joseph Goldstein; Paperback

Seeking the Heart of Wisdom : The Path of Insight Meditation -- by Joseph Goldstein, et al; Paperback

Meditation

The Meditator's Handbook : A Comprehensive Guide to Eastern and Western Meditation Techniques
by David Fontana
Everything you wanted to know about the current practices of different meditation methods

The Complete Idiot's Guide to Meditation
by Joan Budilovsky, et al (Paperback)

The Yoga Sutras of Patanjali
by Satchidananda, et al (Paperback - October 1990)
The source book of all spiritual meditative practices. Little else needs to be read if you can read and understand this classic.