The Lazy Forger has a tutorial on making a model wooden cart.
The Miniature Wargaming Editor
Modeling An Iroquois Longhouse
This photo tutorial offers great instruction on modeling an Iroquois style Indian longhouse.
1862 Campaign Rules
1862 is a set of American Civil War Campaign Rules designed for Johnny Reb, but which could be used with any miniatures rules set.
Sculpting An Urban Wall
A nice tutorial on sculpting and then making a mold of an urban wall.
Basing Trees
Here’s a photo tutorial on basing tree armatures.