What’s in a name?

Because I’m cleaning house today instead of writing (really, as soon as I’m done with this post) I’m thinking of book titles. I’ve read that some writers have chosen their title before they write the book, others haven’t settled on one until right before publication, and the rest, I presume, come up with a title somewhere in between.

I thought I had a title for my current novel, but now I think not. Book titles are important. I know this, and that’s why I’m now concerned that I don’t have one. What if I can’t think of a good title… a great title? Leaving the decision to someone else would be like letting someone else name my child—not something I want to do. I’m wondering, will my title come from the theme, a line in the book, the color of my protagonist’s eyes? So, I have a question for my fellow writers. How do you find the titles for your books?