- Mindfulness in Plain English by the monk Bhante Gunaratana. Probably the most universally recommended book on general mindfulness.
Direct Pointing/Non-duality - These books may help provide a sense of what enlightenment is about, and the direction to lean into.
- I Am That by Nisargadatta. Classic text of transcribed talks, this would probably be my desert island spiritual book. Free audio of the text.
- The Book: On the Taboo Against Knowing Who You Are by Alan Watts. Thought provoking and relatively palatable even for a mainstream audience.
- Be As You Are: The Teachings of Ramana Maharshi by David Godman. A classic, a compilation of many quotes arranged by topic.
- Gateless Gatecrashers by Ilona and Elena (also the free pdf version). Transcripts of conversations with seekers, containing some of the most direct pointing instructions available. If you dare, even more raw and a bit rude at times is Brutal Beginnings (pdf).
- The Finders by Jeffery Martin. This book presents extensive research into over 1000 people considered to be enlightened. We can quibble with some of the assumptions, or about the morality of selling a Finders Course, but at present there is nothing else really like this. There is a free ebook on the associated publication page that summarizes the findings along with general recommendations for practice.
- The End of Your World by Adyashanti. While this could be interesting even for seekers, this is probably most useful for those who have experienced a degree of awakening.
Other readings:
- What is Enlightenment, a collected series of posts by user iamquiet on reddit, from realization.org by way of archive.org.
- The Layers of Depth in Fundamental Wellbeing, many descriptions of various parts of the path from Jeffery Martin's work and the numerous participants in the Finders Course.