how do I reinstall the AOSP music player in KitKat? I bought a Motorola Moto G yesterday,
And the stock Android music player is missing. 
I found an old froyo player that works somewhat but it isn't fully integrated.
I can't switch songs from the lock screen or the drop down menu. And it has advertising in it.

Where can I find the AOSP music player that will run fully in KitKat; with total OS integration and no ads?
The Moto G comes with Google Play Music as it's default music player. You can download it from the play store if you don't have it already.