There are some classic books on the practice of pranayama, the theory and philosophy of the subtle, vital pranic force and Swami   Satchidananda’s “Breath of Life” CD that includes a guided pranic healing visualization.

1. Breath of Life CD: Integral Yoga Pranayama taught by Swami Satchidananda

2. The Yoga of Breath & Sense Control (DVD) by Swami Satchidananda (also available as a downloadable MP3)

3. Science of Breath by Swami Rama, Rudolph Ballentine MD and Alan Hymes

4. Science of Breath by Yogi Ramacharaka

5. The Yoga of Breath: A Step-by-Step Guide to Pranayama by Richard Rosen

6.  Light on Pranayama by BKS Iyengar