You might also enjoy "Guru for The Aquarian Age The Life and Teachings of Guru Nanak." It's more about the origins of Sikh philosophy, which is the foundation of Kundalini yoga as well.
"How to Know God: The Yoga Aphorisms of Patanjali" by By Swami Prabhavananda & Christopher Isherwood is one of those classic yoga books. It's a bit harder to get through and less practical than the how-to manuals.
Also check out the "Man to Man" series of lectures by Yogi Bhajan, available at Ancient Healing Ways. Also his "Master's Touch" book, a bit pricey at $50, but an incredible collection of meditations and lectures in one volume.
Many Kundalini Yoga "meditation" involve movement or yogic postures and chanting, so the idea of meditation presented here is somewhat different than, say, Buddhist Meditation. But they achieve similar ends.
Other Kundalini Yoga Manuals:
Fountain of Youth
compiled by Sumpuran Khalsa, illustrated by Wahe Guru Kaur
www.women.3ho.org (dead link?)
This excellent manual is a compilation of sets from Women's Camp.
Another Women's Camp manual is Kundalini Yoga for Youth and Joy. Unfortunately this manual is out-of-print, and you have to ask around to find a copy.
I love Gururattan Kaur's manual Sexuality and Spirituality. Another great manual by her is "Transitions to a Heart Centered World." She has other great manuals as well. She is located in the San Diego area.
Harijot Kaur has put together a number of excellent manuals. I have four, although I think she has six or more out. Among them are:
Owner's Manual for the Human Body (a must-have for any serious practioner)
Infinity and Me
She has helped Guru Prem Singh write and publish an excellent manual called Divine Alignment. He is one of the few Kundalini Yoga teachers who brings an excellent mastery and knowledge of proper alignment and position to his teaching practice.
Ravi Singh also wrote a great manual called Kundalini Yoga for Strength, Success, and Spirit. I think it may be out of print. It includes short yoga sets that target certain chakras or body areas; these can be practiced alone or strung together to make longer sets. Shakta Kaur has written a number of great manuals, with a number of different publishers. One of her specialties is yoga for children. We had her speak at our teachers' network meeting here in LA, and it left me interested in obtaining and reading her manuals as well.
www.shaktakhalsa.com/ or www.childrensyoga.com/
Gurutej Kaur has created a number of great DVDs, and I'd recommend them as well. www.theblessingscenter.com