the only place i've ever seen a type of betting percentage is at betfair.com....once you click to the game you want and check off market depth it shows amount wagered on each game. It's not exactly what you are looking for but it does give a little direction to how people are betting.
if anyone ever comes across a site like sportsinsight or whatever for soccer they'd be my personal hero for a day.
look for asian sites, i dont remember what the url was, but there were some asian sites that post the % of bets on each side in the big european leagues.