Barratt Breath Institute
Naro Cinema
Self-Realization Fellowship
Temple of Kriya Yoga
Yoga Alliance
Yoga Journal

Recommended Reading 

Inspirational

Autobiography of a Yogi - Paramahansa Yogananda
The Spirit of Yoga - DeRham and Gill
Life Prayers from around the World - Roberts and Amidon
Hua Hu Ching - The Unknown teachings of Lao Tzu - Brian Walker
When things fall Apart - Pema Chodron

Breath Books

The Breathing Book - Donna Farhi
Conscious Breathing - Gay Hendricks
The Dance of Breath - Kathleen Barratt
Science of Breath - Swami Rama, Ballentine, Hymes
Breath - The Essence of Yoga - Sandra Sabatini

Yoga Asana and Philosophy

Yoga the Iyengar Way - Mehta
The Spirit and Practice of Moving into Stillness - Erich Schiffmann
Awakening the Spine - Vanda Scaravelli
Yin Yoga - Paul Grilley