Directories

So, why don't we have e-mail and cell phone directories yet? I mean these aren't new technologies. People have been talking about directories for ever, so why don't they exist yet? Is it because Corporate American can't cooperate and compile their information together? You know the information is there. I'm sure it's all sitting on some data bases in some server closets across the country/world. With a few clicks of a button, I'm sure that all the information could be combined. One of the first things we teach children is to share and to cooperate. Why in the world can't we get these companies to just love one another? Or is there a good reason that I'm overlooking?