So, I'm writing a paper for my IT class on digital delivery services, specifically focusing on Apple iTunes store and Valve's Steam platform. I'm a Mac fan so of course every time there's a new webcast for one of Steve Job's presentations I watch them. Now, he quotes how much Apple has earned via iTunes, how much music they've sold, how many labels or TV networks are signed on to sell their products via iTunes, etc. Where is a reliable place to get information like that? Like I said, it's for a IT paper, so I imagine any reputable publication or e-commerce journal would work. But what about websites?