http://www.eplindex.com/17609/dirtiest-players-and-teams-league-stats-comparison.html Ignoring strikers, Adam, Song and Fellaini get the Mr Nasty Awards.
I don't think that comparison really gives a true indicator of who's dirty. Holt's physical and combative, so he'll give lots of fouls away when challenging for headers and hustling defenders, but he's not really dirty, for me. Barry and Cattermole are level, but I think that we all know who's more likely to make a filthy challenge. City give away a lot of fouls when they're not in possession because they're cynical. They lose the ball and take someone out to stop the break.
Karl Henry was arguably the dirtiest in the league. It depends how you judge it, whether it's dangerous tackles, cynical fouls, diving, etc.
Strikers tend to foul differently, pushes and tugs to gain a small advantage. Defenders/defensive mids tend to be the cynical ****ers.