This is what you've all been waiting for!
Many of us use Photoshop or Photoshop Elements, however many are looking for a free program to help add a watermark to your images or to help resize them.
Here is the solution (recommended to me and SUDSOL originally from Erika Martin) - FastStone.(http://www.faststone.org/FSResizerDetail.htm). Click to download it to your computer.
Once installed, open/run the program. The following instructions are on how to resize and add a watermark to an existing image. This program can also do other things such as cropping, but this tutorial is covering resizing and adding a watermark but please have fun experimenting on your own as well.
Other related tutorials on image editing, creating and adding watermarks: http://www.blogsbyheather.com/image_editing/
Hope this helps!