is this defamation of character?

if you go to the craigslist "comp" forum, the thread that starts off "holy crap" is an image someone created and posted about me.

the other day someone in there also posted my full name, a picture of my wife and i at our wedding after googling my forum name and asked if it was me in the picture. im a bit frightened at what i have seen in there. but im more upset at the picture that was posted of me and want some input from my yahoo answer pals ;)

and im quite aware this happened in a forum, but, because my question is about (defamation of character) im not posting this under computers and internet, as the topic is not about the internet. im sure someone will tell me where to post and thank you ive considered it.