The post comes up with video previews of the said song used in Arashi TV Show/whatever, the mp3 download link, and the mp3 in a player so you can listen to original dirrectly before downloading.
Also, there's a request list of songs that I yet have to find, so if you're willing to help in this, the more we are, the more informations we'll get ^^
( This is embed photobucket videos heavy )