Nine Inch Nails' 37 Ghosts & 38 Ghosts were NOT released on the CD, Blu-Ray or official download. These two tracks are exclusive to the multi-track DVD. You can find the original multitrack files here. A high-definition audio rip of the Blu-Ray can be found here.
Copyright : Ghosts I-IV is licensed under a Creative Commons Attribution Non-Commercial Share Alike license. (source: http://ghosts.nin.com/main/faq )