Ironhands has a tutorial on building a Games Workshop type Thunderhawk gunship from styrene and bits of toys. It’s a nice and imaginative scratchbuilding project.
modeling
Making Eldar Terrain For Warhammer 40K
Ironhands has a page with tips for creating sufficiently alien Eldar terrain for your Warhammer 40K games.
Wrecked Cars In Plaster
Given all of the Zombie gaming going on these days, there’s bound to be a demand for models of wrecked cars. Terragenesis has an article on making casts of car wreckage in plaster.
Making Silicon Molds
At A Year of Frugal Gaming Blog, the author has an illustrated article on his efforts to create a silicon mold to allow him to replicate various architectural parts for terrain making.