This is a great video on modeling an abandoned farmhouse or shack for your wargames table.
modeling
Making CD Based Scatter Terrain Bases
Making Simple World War II Buildings
Matakishi has some instructions with photos for making World War II era buildings out of sheets of cork.
Making Ice Floe Terrain
Terrain Thralls has a photo tutorial on making terrain that looks like ice floes. They’re cleverly made from foam core, and is intended for Privateer Press’ Warmachine game, but I think it would be spectacular in a variety of fantasy settings. I can also envision a neat Frankenstein vs The Monster scenario.
Using Sculpey To Model Slate
Sculpey is a polymer clay that hardens in the oven at relatively low temperatures. It’s amazing stuff that can be used to create a wide variety of useful things for wargames. Here’s a tutorial on using sculpy to model slate.