Copyrights seem to fall into two rough categories, the signatures where name and copyright info appear on the pic but could be removed or cropped out and the overlays which place large blocking symbols over the bulk or key parts of the image. You can also add copyright info in the EXIF data of jpg a few other file formats by using the File Info from the File Pull-down menu in PS.
I never much cared for the overlay look but it is more important if you are selling your work and this action shows how you can setup layers to get a semi-transparent watermark over your images. You can also setup your own brush and apply layer styles and blend modes to get your own custom effect that is repeatable.
Link to Copyright Brush by Brian James (Scrool down till you find it and info on loading is available at the site.
"Brian's action creates a transparent copyright watermark as a brush. One action creates it, the second implements it. You then have the brush available to you from the brushes palette. Increase or decrease the size as you would any other brush. You can also reduce opacity to make it more or less subtle."
