Mukul Dube , Sep 27, 2010; 08:15 p.m.
There's two approaches to this, and you can use either one or both. One is to embed IPTC metadata into the photo file itself. This will not be visible on the photo but can be viewed with software that supports it. The other option is to have a not too intrusive but visible overlay on the photo, something short like "(c) Rachel Dean". For this you must work on a copy so that the original is not affected. I do not know if these things can be done with Photoshop Elements.