http://www.uelsmann.net/ This is my all time favorite artist Jerry Uelsmann, he combines multiple images in the darkroom. He started doing this long before photoshop and is amazing at it. I hope you all visit the site and enjoy his work as well.
p.s. Im still learning when it comes to working my mac so thats why i just posted a link, I was having a lot of trouble saving an image to my desktop and then posting it, kinda bad I know but thats why there is no picture.