Thank you Trish and Michelle!
Trish - I actually have Dover's Celtic Designs for Artists and Craftspeople, which has some good symbols in it, but unfortunately, no Green Man.
The link you sent had some lovely motifs as well, but again, no GM. I did book mark it though, for future reference!
Michelle - That was a beautiful pencil sketch on the flkr site! But unfortunately a little too "sketchy" for what I was looking for. Boudicca's was gorgeous, too.
I did some more searching, and finally found this site:
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