add logo in iPhoto?

[DanielleGoodPhotos]

For anyone who has iPhoto, do you know how to add a logo to pics? I don't have iPhoto '09 yet, so I'm wondering if it's even possible. I feel like I've looked everywhere. If it's not possible, is there a different way to add it? Thanks!

 

[mtaylor]

I use a free progam called PicMark. I can't imagine iPhoto having any awesome intuitive watermarking function.