For their Mars Attacks game, Mantic released sets of 20th century style brick ruins. They’re good looking, but with a little work can be even better.
Modeling
Making Hedges With Plasticard and Clump Foliage
Here’s another tutorial on making hedges — useful for lots of different settings.
Making Ruined Roads from Vinyl/Lino Tiles
The Tabletop Terrain blog has a useful article on using vinyl/linoleum tiles to make roads appropriate for a combat zone or post-apocalypse setting.
How To Make Craters
This video tutorial teaches a technique for making craters. It’s a useful thing for modern, post modern and full-blown science fiction games.
Texturing Wargames Scenery Bases
Following up on a previous tutorial on making a gloop to apply texture to terrain, The Terrain Tutor vlogs on additional texturing options.