Here’s a good tutorial on working with tree armatures.
Modeling
Making 15mm Hedges
Here’s a tutorial on making a 15mm hedges.
Cutting Form Hills Tutorial
Here’s a useful tutorial on cutting foam hills.
Old West Buildings Tutorial
Cowtown Chronicle offers an extensive tutorial on building Old West buildings.
Quick and Easy Bushes
Here’s a method for making some really nice bushes for your miniature wargames.