Water Mark

I think I am in the right place to ask this, if not please forgive.....

I am looking to add a watermark to some photos. The only software that I currently have is Adobe Photoshop Elements 5.0.
Is there a plug-in. I have not seen were I can add it in the software.....

Any help would be greatly appreciated

i've never used elements, but if you can do actions and batch processing, you should be able to make one action doing the watermark you want, and then batch the whole lot of them