i want to know too!

this looks like an illustration, not a font; but you can find similar graffiti fonts here: http://www.dafont.com/theme.php?cat=606&page=1&nb_ppp_old=10&text=Type+your+text+here&nb_ppp=50&psize=m&classt=pop

yeah, not a font

Take a look at
http://www.graffitifonts.net/
and
http://new.myfonts.com/search/tag%3Agraffiti/fonts/?sort=abc