Another thing you can do to protect from people simply cutting and pasting your design is use a water mark program and put a mark across the design. That way at least they would have to work harder at simply copying it and using it. Here is a link to a pretty cheap one that works well
Script Software - Secure and Protect Your Digital Photos with iWatermark. Hope this helps. I myself keep telling myself I am going to start using a watermark but always forget
