Here is a terrain piece I have been working on, using my old, damaged LRC, a piece a cardboard, some sand, some Citadel razor wire and some glue.
How did I build it?
Step One, take assembled Land Raider, cut out rough chunks with a saw, then, after highlighting, washing, and applying rust/battle damage, take a cotton ball, place it in the opening formed by the hacked off pieces, and set it on fire. Let it burn itself out, and you'll get a nice melted look to the side of the vehicle that you want to look liker it got hit by a melta.
Step Two,cut out a large piece of cardboard, and cover in white glue, then continually apply layers of fine to course grain sand, keep applying it till you have good cover, and wait for the glue to dry.
Step Three: Take some super glue, krazy glue, or any other powerful adhesive,and plop the LRC down wherever you want it to got, then apply extra bits and pieces as you see fit.