Mike -- For background i'm attaching pics of some of the background i did behind some factory buildings. Some of them were just painted on, others done either on Strathmore board, some on 1/8" or 1/4" foam core. I used brick paper glued (3M Spray 77) to the backing in most instances. It all gives the illusion of depth. Don't restrict yourself to one material or style; mix it up.
Another place you might want to look for materials (brick paper, etc.) and ideas is Clever Models.
