A client of mine had similar concerns and after much research I agree that
copyscape seems to win hands down.
Essentially once your work is in print, you are considerd the copyright owner - so simply place a line of text stating so.Unfortunately there will always be applications that provide a way of lifting content and transferring it elsewhere - even if you password protected your site - so it's not really
worth getting too hung up about - it obviously means that someone considers your work more worthy than their intelligence. However you can have great fun with the
SEO aspect!
Good luck with your site