The Radiance Sutras by Lorin Roche. Its Roche's intepretation of Vijñana Bhairava Tantra and is poetic. Every word is delicious and savory.
These two stand out, will add more later.
Edit:
The Upanishads- Eknath Easwaran. Bhagavad Gita. Man's Eternal Quest- Paramahansa Yogananda. Daniel Odier- Tantric Quest: An Encounter with Absolute Love. Daniel Odier:Desire: The Tantric Path to Awakening. The Tibetan Book of the dead. Roy Eugene Davis:The Path of Light. Swami Kriyananda: Awaken to Superconsciousness. Sally Kempton- Awakening Shakti: The Transformative Power of the Goddesses of Yoga. All of Yogani's books.
I agree AutoBio of a Yogi is a must read (the movie doesn't cut it) I have a lot of favorites- for some reason I'm remembering the book Ishmael - that was really impactful in getting me on a spiritual path...Peaceful Warrior was great as well as Journey of Socrates both by Dan Millman.
Paul Brunton - Secret India Hermann Hesse - Siddhartha & The Glass-Bead Game Mircea Eliade - pretty much everything he wrote, fiction and non-fiction Milarepa The Tibetan Book of the Dead (or better translated "The Great Book of Natural Liberation")