I'd like to enquire with the Facebook heads on here about how best to do the following:

I'd like to run a promotion from my Facebook business page that encourages users to recommend a friend in order to gain access to enter a competition. Obviously being in the Facebook environment it would be preferred to encourage Facebookers to refer friend's on their profile. Anybody know if there's an app out there (I've searched and not found) that does this? Does the Facebook API allow access to select specific friend(s) to notify on Facebook?

Thanks for your help & suggestions.