Number one thing I hear when I tell people the title of my book, Being Human: There's a TV show already called that. Are you sure you can use the same title? At first I wasn't sure but I've been doing a little digging and have discovered an answer.
Titles, I have discovered, can't be copyrighted. When you copyright something, you copyright the work, not the title. A title of a book usually isn't trademarked either, series are more often the thing trademarked. Like Harry Potter. Harry Potter and the Sorcerer's Stone isn't trademarked but Harry Potter as a series is. Both trademark and copyrighting aren't required for authors. They are just added legal protection - something possibly useful in terms of people stealing your work and profiting from it. I found this article to be very helpful: Can you trademark your book title?
I also found this on Yahoo answers about different medias with the same title. As you can see, it doesn't matter if there is a TV show called Being Human. I can still use that as my title and since I have no plans on making Being Human the name of a series, trademarking it would be pointless as well. If I understand correctly (meaning not 100% sure but pretty confident I do understand,) by not doing those things, I'm making it clear for others to use Being Human as a title as well. I trademark something then I take that option away from another.
And if you search Amazon, you find books with the same title. I did a search for Enclave and as you can see there's multiple books with the exact same title. The only downside is it might confuse the reader. If they don't know the author's name, they might grab the wrong book! So it's still a good idea to do a search on your title, see if anyone else uses it as well. Doesn't mean you have to change it but I think it's a good thing to be aware of. Just do your research, find the answers to those tricky legal questions and make sure you don't set yourself up for heartbreak later.