Ringtone content can only be submitted by creating a ringtone release within TuneCore. The ringtone must be pre-cut and cannot be distributed as a selection of tracks on an album.
Apple is no longer accepting ringtone content in the iTunes music store application accessed via computers. Ringtones are only available to users as a "Ringtone product" via the iTunes mobile device store on iOS devices (the iPhone, iPod Touch or iPad).
Learn more about distributing ringtones to iTunes.