I did forget to mention that pretty much every computer, at least every one I've seen, includes Microsoft Paint which will also add text over an image.

I was at home and didn't want to go into a long description of Picture Shark (still don't )

You open the image, you then open a signature image (or stamp or whatever you want to call it, your name and copyright / website information...) click on the background of the second image, and everything disappears, except the lettering, and then set the feathering, opacity and transparency, and it creates a new file with the two images combined.

You can place the stamp at nine points over the original and it has adjustments, so virtually anyplace, and you have complete control.

It can be made to be almost invisible, but cover the middle of the image, so if someone decides to use your scan, your name is on it. At the same time, unlike plain text, it doesn't take over the viewing enjoyment.

This isn't a one at a time deal. If you select all images in a directory, it will stamp all of them in a batch. The idea is that once you make an overlay, you can just click a few times and Zing it's done.

Next time you want to stamp an image, it remembers all the settings, and click, click, click, you're done.

Here's a subtile example.