Wallpaper, but not desktop

1

I am trying to figure out how to make wallpaper, but not the desktop background kind. I want to make a background for my webpage that looks like old school wallpaper. Like on this site: http://www.onlineclassical.com/ I am refering to the grey areas on the left and right of this page. Any one know a tutorial that teaches how to make this in Fireworks or PSP? All searches for “wallpaper” bring up desktop wallpaper, and I don’t know what else to search for.