I don't know of any game sites that give out that information, but you may be able to ask them directly if they have some kind of API you can tap into. For example, contact Zynga (developers of popular Facebook games, such as FarmVille, CityVille, etc) and ask them if they have an API for developers to retrieve stats on their games. You could write your own module to easily extract that information via json, XML or whatever format they use.