I dont mind spending some money to get the right product, I use a iMac computer so I will need whatever the best software is out there to be compatible with Mac................any recommendations???If you want free software that does it then try faststone picture viewer. The effects->watermark menu is what you want.
I'd have though most image processing software will do it tbh.
It is a bit of a double edged sword as Scott has said, it is nice to get your name recognised but they do tend to spoil the the image.
Toby