For the more craft oriented among you, here are a few videos to guide you through making some plasticine modeling clay figures for the Crusades.
Modeling
Modeling Grapevines
18 Charlie has a photo tutorial on making grape vines for 15mm games.
Making Bocage Tutorial
The 18 Charlie site has a nice photo tutorial on making bocage for your 15mm wargames.
15mm Palm Tree Tutorial
18 Charlie has a tutorial on making 15mm palm trees. The methods looks good, and should be quick and inexpensive.