Legio Wargames has a tutorial on basing your figures with wood filler, sand and other bits.
Modeling
Making Hedgerows
This Very Blog has a very good set of instructions for building hedgerows for 25mm – 28mm figures. This is the best set of instructions I have found, and the one I will use for my Normandy terrain.
Modeling Trees For The Great War
The Wargames Table has a nice article on modeling trees for The Great War. The trees also look to me as though they would be nice for a deadlands type of fantasy setup.
Weathering Techniques For Models
Alfred Wong has written a guide to weathering your plastic models. This is useful stuff — especially with the wide variety of resin and plasic vehicle models being used in games today.
Making A Wargames Mat
This video from Red Beard Baron is a good tutorial on making a wargames mat from cloth, cauking and flock.