The 1000 Foot General blog has a good tutorial on building rocky desert hills that are suitable for a wide variety of settings.
modeling
Casting Toy Soldiers In Pewter
The Toy Soldiers Forever blog has a video on proper techniques for casting your own toy soldiers from pewter. He also suggests some cheap sources of the metal.
Precision Cutting Foam For Terrain Boards
The Terrain Tutor has a very clever method for cutting precise sizes for terrain boards.
Building A Dark Ages Frame House
The Man Cave has some tips on how he built a nice looking dark ages frame house.