Back to books? :)
Reading "Opening Up:" others have mentioned it and it seems standard fare in Poly reading these days.
I'm also reading "The Ethical Slut" and while Luv and I do have *monster* libidos I consider much of the book to be parenthetical to my poly thinking. Focused *entirely* on what I feel is a wonderful *part* of the experience.
Here are two that are not primarily poly but about self and relationships and I feel they are going to help greatly. Both give a nod to the fact that the relationships to which their techniques might be applied do not have to be standard monogamous in nature:
"Boundaries and Relationships" by Charles L. Whitfield, M.D. - Subtitled "Knowing, protecting and enjoying the Self" about figuring out what you really want and being able to stand by that and communicate it to others.
"How to be a couple and still be free" by Tina Tessina, Ph.D and Riley K. Smith, M.A. is (in my mind) a continuation of the boundaries book in that it is about negotiating and designing the relationship that you want in combination with your partners. Which as I see it is the next step after actually figuring out what you want, and why.
"On Love and Loneliness" by J. Krishnamurti - a series of dialogs investigating our intimate relationships with ourselves, others, and society. This book operates at a very metaphysical level that I enjoy, but may offer less in the area of tangible practices or real life situations.
The "Tao Te Ching". Philosophy of how things work at their most basic level. It works to keep me grounded and centered and understand the things that happen as natural and part of the flow of life, now matter how tumultuous they appear to be.
Not a book, but I'd always recommend some form of meditation activity. Benefits accrue in almost every area of your life if you can reset your thoughts once or twice a day.