In this book-Ecstasy: Understanding the Psychology of Joy, Jungian analyst Robert Johnson explains how we have lost our capacity for ecstasy and joy--and how we can regain it.
Here is one of my favorite books on following your passion and finding work that you love.
This book is very helpful if you are transitioning from your
current career to one you are passionate about, especially when you are
taking a income cut (not at all uncommon, and obviously quite tricky).