The Four Agreements
by don Miguel Ruiz
If you want one book that offers a general handbook for living, this one might just be it. “In The Four Agreements, Ruiz reveals the source of self-limiting beliefs that rob us of joy and create needless suffering. Based on ancient Toltec wisdom, the four agreements offer a powerful code of conduct that can rapidly transform our lives to a new experience of freedom, true happiness, and love.

1. Be Impeccable With Your Word
2. Don’t Take Anything Personally
3. Don’t Make Assumptions
4. Always Do Your Best

Also worth browsing (by don Miguel Ruiz):

• The Fifth Agreement (with don Jose Ruiz)
  “Be Skeptical, but Learn To Listen”

• The Mastery of Love
• The Voice of Knowledge
• The Four Agreements Companion Book (with Janet Mills)

I Could Do Anything If I Only Knew What It Was
by Barbara Sher
No matter what your age, no matter how “unattainable” your dreams … You can create — and live — a life you love! So says Barbara Sher, and she sets out to show you how to do that in this book. “I Could Do Anything If I Only Knew What It Was guides you, not to another unsatisfying job, but to a richly rewarding career rooted in your heart’s desire. And in a work of true emancipation, this life-changing sourcebook reveals how you can recapture “long lost” goals, overcome the blocks that inhibit your success, decide what you want to be, and live your dreams forever!”

The Happiness Project
by Gretchen Rubin
“Or, Why I Spent a Year trying to Sing in the Morning, Clean My Closets, Fight Right, Read Aristotle, and Generally Have More Fun.” This book is Rubin’s account of that year. It’s fun, surprising, intriguing, and will certainly set you thinking about what it takes to be happy and how you just might be able to achieve that goal.