This video has some good tips for making industrial scatter terrain for your wargames. Proper scatter terrain makes a huge difference in teh visual interest of a gaming tabletop.
Here are some good instructions for building modern wood yard fences.
If you are playing miniature wargames set in the Sudan, you’ve got to have a redoubt. Steve Winter has a very detailed explaination of how to build one.
Germ’s World has a large number of 25mm modern buildings for you to download and use in your modern miniautures wargames.