Hello mrsb,
You can register some rights and files on your website for free using a creative commons license and then upgrade it to a premium full copyright service.
http://creativecommons.org/
Or register all your publications, files and even your very own words but I am telling it is a lengthily progress.
I found a great article on how to get your website copyrighted fully it does explain it in simple steps.
http://www.lawgirl.com/webcopyright.shtml