Yes it does become copyright to you as soon as you design / write something, however in a court of law, it makes it a lot easier to prove that you are the origional creator.

The best thing is to just send a copy to your lawyer and yorself. Your lawyer can date and file it and when you recieve it from the one u sen yourself, DO NOT open it. Leave it unopened. This is because there is a post date stamp on it and so if it is left unopened, if you need to in court, you can open it and say that you made this on "XX.XX.XXXX".

However at the end of the day, unless you are willing to spend a lot of money in fighting your case, there is very little you can do out of court.