The Hour of Wolves and Shattered Shields blog has an illustrated article on making armatures for miniatures sculpting.
Modeling
Making Flexible Roads
Tabletop Terrain has a tutorial on making flexible roads for your 15mm miniature wargames out of weed fabric and liquid nails.
Advice on Modeling Rivers
Tim Marshall has some advice on modeling rivers and other bodies of water. There are some very good ideas here.
Cheap and Easy Rail Fences
The “My Wargaming Blog” has an article on making cheap and easy rail fences.