These days - a lot! It's part of the marketing, and if you can't come up with a snazzy, jazzy title that will just zing your book off the shelf (note the ZZZs) then the publicity department will do it for you. I first got clued in to the whole title thing when I was writing poetry. If you know anything about poems, you know all the things that a title can be: it can act like the first line of the poem; it can act like a label to signal what the poem is about; it can be like a line of the poem that adds more meaning; it can clue the reader into other layers of meaning. In short, a title for a poem is important, and if you call your poem Untitled you are either missing out through ignorance, or you're lazy, or you're trying to be obscure or clever (duh). At least, that's what other poets will think, because we all spend a lot of time on titles. It's important. It's worth the time.
What made me think about this topic? A visit to Borders. I love my independents but when you want to wallow in a huge range of choices and spend ages just looking, Borders is it. And the coffee helps too. But I found myself in front of the New Releases shelves, and in particular, the new Nonfiction section. Which in this part of the store, was 90% memoirs. I don't read a lot of memoirs (although I am reading Truth and Beauty by Ann Patchett right now and loving it) but even so, a scan of the books made me shudder. Because of their titles.
I should have gone back with a piece of paper and written them down, but this is kind of what I saw. Six shelves of display copies, many with pastel covers and foggy photos. And the titles went like this: Shattered, Lost, Beyond Hate, It Wasn't Me, Left Behind, Scarred, Child No More, Not My Child, No Mother For Me, etc etc. I had never seen them all lined up like that before, and it was awful. I am sure that every single person who has written a memoir like that has important, heart-wrenching stories to tell. But I'm not going to be reading them.
A couple of years ago, a critic called them "misery memoirs". Can't you tell by the titles? So I went onto Amazon and did a search on "memoir" and what a much cheerier list I found! Are You There Vodka: It's Me, Chelsea, Half-Assed: A Weight Loss Memoir, When A Crocodile Eats the Sun, Running With Scissors, and Never Have Your Dog Stuffed. How jolly are they?
Sometimes my titles just come out of the blue before I even start the story. The Too-Tight Tutu was one, Tracey Binns Was Trouble was another. As for Sixth Grade Style Queen (Not!) - I couldn't have developed that afterwards - it was another one that popped into my head and wouldn't go away. But i do think that years of writing poems and being aware of what a title can do has made a big difference. My current novel has been without a title for several months. Then someone asked, "Doesn't it have a title yet?" And after a few minutes of serious thought, now it does.
A title is important. A genius title can help to sell a book. It's part of that instant attention/ gratification thing we have going these days. If you're not sure about your book title, there are a few things you can do. Brainstorm ideas, look on Amazon or B&N for books similar to yours and try to come up with something different, look at anthologies of poems and see what poets have achieved, make yourself write down 20 possible titles and test them out, use your thesaurus and your friends and anything you can find to come up with word associations. Imagine seeing your book in a catalogue or in publicity material. How do you want it to sound? Look at other book titles and say them out loud. What appeals to you? Does it convey the tone of your book? Try whatever you can to find a great title - it's worth the effort.