Question: I have the idea for my book but I can't think of a title but I was wondering do I need to come up with a title or does someone else do that or do I come up with a title and if the publisher wants they can change it?Answer:
Generally, the last word on titles goes to the marketing department of the publisher. The reason is that titles are an important marketing tool. The publisher wants a title that will ideally attract the readers most likely to enjoy the book.
Books in a series should have similar titles because, if the first book sells well, similar titles let the fans know the other books offer them more of the same. For example, all Kelly Armstrong's paranormal books have one-word titles. Sue Grafton's murder mysteries follow a set formula: A is for Alabi, B is for Burglar
For similar reasons, lots of paranormal books have the word "dark" in the title (if not "wolf" or "vampire"). Romances often have words like "love," "forbidden," and "temptation." When the space program was new and exciting, it was very common for science fiction books to have words like "star," "spaceship," or "alien" in the title - but not so much any more.
Of course, there are no absolute rules and plenty of titles don't follow such formulae.
It doesn't hurt if you have a title you think makes the book sound appealing to its ideal reader, because that title will appear in your query letter, so it is a tool for you to use to get the interest of agents or publishers.
However, while you are working on a book, all you need is a working title - something that distinguishes it from all the other stories you may have written. You have plenty of time to change it if you get a better idea.