Copy right is automatically granted to the author by simpley using the (c)copyright (username) year, that grants you protection over your work, but if your serious, you might want to consider, trade marking all your work such as the characters, their names and the places they reside in, this is a more enforcable level of protection for you, but it costs, how much I don't know but if the stroy flys it could be worth a lot, just look how Shrek started...