Just to add a couple...
"Living With The Himalayan Masters" by Swami Rama
"Play of Consciousness" by Swami Muktananda
"The Teachings of Ramana Maharshi"
"The Knee of Listening" by Sri Adi Da (Franklin Jones)
My Shakti description is from the viewpoint of Advaita Vedanta, and is Shaivite by tradition. Shakti is not considered in any sense the lesser. It only states that whatever arises on whatever level is Shakti. Shiva does not appear. If manifestation appears at the level of duality, it is...
I've always heard the Divine Creative Energy referred to as Shiva's Shakti. When speaking about all forms of manifestation and Maya (the delusion of difference/separation), the seeker is relating to Shakti. Once Maya has been revealed (enlightenment), Shiva is the Revelation and His Shakti...