Try Power of Now book. Yoga when seen beyond the scope of american strenous-ism is a practice of body stillness, mind, and heart. Staying in the present moment is a part of this. From that place all the stretches come naturally and flow. If you don't have the first part then your not doing yoga, just stretching.
Try the book Yin yoga, The Power of Now, and amazon.com has Chakra Yoga, and yoga for dummies.
