Watermarks

Ok I know I should know this but it's eluding me! How do I add a watermark to a jpeg? Am happily adding my website to the bottom but actually I think it's safer to just slap a watermark across the middle so it can't be cut out. Is there an automatic way of doing this so I don't have to edit each and every photo?

I used to know how to do it, I think you can make a brush in photoshop with your sig etc on it. Again I still can't remember how as it would save me lots of time. Not much help am I sorry.

I've never done it, but know that on Mr Site one of the upload options for photos is to add a watermark.

Hello

For watermarks I use Photoshop and add a layer, but I came across this link. I haven't tried it though.
http://www.watermark.ws/

Nice link Zen will have a go soon as I'm going to re take a few photos