Fill in the form:
http://support.chess.com/index.php?_m=tickets&_a=submit
Chess.com takes these matters very seriously, in my experience.
p.s. Take a screen shot, in case he returns and deletes the note he made on your homepage.
p.p.s. Block that member: Homepage >> Account >> Manage privacy settings >> add his handle to your list (bottom of page).
He will be unable to post anything further or message you.
I recently had a game with a guy who left with 5 mins to go and one move from his checkmate. So i posted on his note spot "nice job losing". It really irritates me when they abandon and I have to wait. there is a resign button.
He posted on my site "you talk too much.... nigger"
His name is Levile.
This shouldn't be acceptable in any book!
what can i do about it?