I started out looking for images of the Green Man and ended up collecting some interesting information:

Whiterock GreenMen Sculpture
Looking for representations of the Green Man for a painting, I came across this site. Note that there's a link to the studio webcam. Could be interesting.

Green Man - Wikipedia, the free encyclopedia
Exploring the significance of the Green Man...

The Mythology of the Green Man (article) by Gary R Varner on AuthorsDen
A scholarly article by Gary R Varner on AuthorsDen--it's an excerpt from "The Mythic Forest, the Green Man and the Spirit of Nature."

At the Edge: Articles on archaeology, folklore and mythology
The link title says it all. This article is titled "The Green Man: Variations on a Theme."