Figured I'd post my top 10 separately. Here they are in no particular order with a little blurb about each:
1. Nature and the Human Soul: Cultivating Wholeness and Community in a Fragmented World, by Bill Plotkin
Has got to be one of my all-time favourites as he speaks a great deal of sense. This is a book that sets forth a model on how we can as individuals and as a society move beyond patho-adolescence and self-destruct mode, from an ego-centric worldview towards an eco-centric worldview that re-establishes right relations between us and soul, as well as us and nature. In my own life, the stages he talks about are bang on with my own experiences--particularly in how he mapped the "Wandering" stage and the "Soul Apprentice" stage.
2. The Practice of the Wild: Essays, by Gary Snyder
If you want to read a book that will profoundly alter your views of nature and the wild, and your relationship to it, then this is the book to read. It is practical ecology (thus the 'Practice of the Wild'), from an ethical and spiritual point of view. Gary Snyder I see as one of those trail blazers, fluidly and fluently pointing us in the direction of the future. This collection of essays ranges on numerous important topics relating to our relationship to nature and to life itself.
3. The Spell of the Sensuous: Perception and Language in a More-Than-Human World, by David Abram
Another mind-blowing book. On the surface, this book examines exactly how we perceive the world and how language shapes those perceptions, but it really is so much more! In examining the nature of human perception and language, he also branches out into some very tough subjects like "where the past and future exist, the relationship between space and time, and how the written word serves to sever humans from their primordial source of sustenance: the earth." A very well-researched, academic work. (quote from Amazon reviews)
4. An Emerald Earth: Cultivating a Natural Spirituality and Serving Creativity in Our World, by Felicia Norton and Charles Smith
Rooted in Sufi mysticism, this book is a well-rounded, grounded approach to understanding the "self" and "God"--and connecting this understanding to the natural world and our "natural being". It has a number of meditations and at times resonated greatly with different Eastern traditions like Buddhism and Daoism.
5. The Salmon in the Spring: the Ecology of Celtic Spirituality, by Jason Kirkey
Not really a book about ancient Celtic religion--instead a modern approach to the Celtic mythos and landscapes, as a way of orienting ourselves in the cosmos and finding ways to heal and transform our lives and our societies. Although "Celtic"-focused, there is a lot of Buddhist influence and I appreciate his honest and humble approach. A pretty rare work.
6. The Spiral of Memory and Belonging: A Celtic Path of Soul and Kinship, by Frank MacEowen
My favourite of Frank's three books. It also is a modern approach to Celtic story and place, but is also just as much about shamanism and the process of soul-initiation. His model of the spiral of initiation makes a lot of sense to me, and helped me when I was at a very bad place. My other favourite part is his focus on the role of the dead and the Ancestors in our lives--and how our understanding of Death directly influences how we live today.
7. Nothing Special: Living Zen, by Charlotte Joko Beck
Wow. What can I say. This book showed me a whole other way of being in the world. This was the book that finally got me meditating every day, and her basic, didactic explanations on meditation, the mind, zen, the nature of reality, unconscious judgments and thoughts, "now", etc are worth every second you read them.
8. A Brief History of Everything, by Ken Wilber
I couldn't *not* mention Ken Wilber. Sometimes he aggrevates me and other times I adore him, but I think everyone should read at least one of his books and have an understanding of what it means to be "integral". This particular book is--well--like it says--a brief history or examination of everything as we know it, the universe.
9. Wild Love, by Gill Edwards
Although on the surface, this book may appear shallow, but to my surprise it is far from it. Her ideas about wild (unconditional) love versus tame (full of expectations) love are pivotol--tying our concepts of love to our understanding of God. She examines ego-filled, need-based co-dependent relationships and discusses how we can heal ourselves through -- love. This is probably the most "New Agey" book in my library, but I think that once you begin to read it, you may see your own patterns of relating to others and yourself--and such a realisation is not one to miss because it could dramatically change how you approach both romance and spirituality.
10. The Idea of the Holy, by Rudolf Otto
Last but not least, this translation is the book where Rudolf Otto first discusses the concept of the sacred or holy, and where he coined the term "numinous". This is an important work which I think will deepen any beliefs or path.