You can't quit a job when you don't have one. But it doesn't stop you from pursuing a "dream job," does it? The book, Quitter, by Jon Acuff is a good one. Really, it attacks all of the reasons that people (this may or may not be applicable to me) use to not pursue a dream.
His #1 point, "Keep your day job" is especially easy for me because my day job is to be a mom. And I'm not quitting that no matter what.
I don't know if it was the next point in the book or not, but it was the next "biggy" that I got, which is--you must pursue your job around your other obligations. Unlike the author of Eat, Pray, Love, we're not getting paid to travel around spending months in secluded areas and write about our experiences. (In defense of the EPL author, I have never read her book, but I did see her twice on Oprah.) We have spouses, children, bills. We have to decide how to do what we love around and with who we love.
There's plenty more that I want to say, but 1) I have not yet finished the book and 2) Wendell is waiting for me to come to bed.