There are ways to get DLC games and play them on your xbox 360 using gamesaves, but you need the plug to hook it up to your console. Plus that would be a good way to get banned I would assume.
It IS possible I would guess since other DLC/Demo's have been done, but I have not seen anyone upload any so I doubt you will find any.
There are various "Track Packs" like Country, AC/DC, Metal, etc. that you download the game iso's for and burn, but I am sure you don't mean those and are talking about the single DLC songs.
This post has been edited by AllSewnUp: Yesterday, 02:22 PM