Now this is going to be another sort of "Look at other people's work!" post. Just remember folks, this blog is as much for my benefit as yours.
Battlefront has some stellar articles. The hub on their website is if you click on "Modeling" on the dropdown menu of "Hobby" at the top of their site. Here's a direct link. The ones to look out for are No Business Like Snow Business, Using the Rural Bases (if only for how they're flocked at the end of the article), Plastic Bases: Urban Rubble (for you folks who think you can do some of that stuff from scratch or want to see all that you can cram onto a FoW base), and one that isn't accessible through that list of articles, Desert Basing, which is an unbelievably awesome article. It showcases the variety of deserts and how to represent that on your bases.
There's even more basing goodness to extract from Battlefront's site. For that, you'll need to go to Hobby --> Painting, and look for the winners of painting competitions. For instance, the 2011 Iron Cross painting competition winners and another Iron Cross event. One of my favorites is the mortar platoon with the fences, which is what made my give it a go for my Americans. It didn't turn out as well as my reference (1/8" squad balsa sticks are way too thick for 15mm, FYI), but hey, it's good nonetheless.
Games Workshop has a really awesome snow basing article, believe it or not. Maybe the bases for my Finnish infantry would tons better if I had bothered to research for this article! D'oh. Unfortunately GW has taken down the direct links to all of these, so you have to find them via some judicious Googling. Best of luck trying to find anything else on there!
Last but certainly not least is one of my favorite blogs for hobby tutorials: Massive Voodoo. I'm going to link to their tutorials on Basing (read them all!) since that is relevant to the article, but the rest of their site is stupendous as well. These are the kinda guys who paint for Golden Demon competitions. Lots of hyper realism.
That's all I have for you!