Japanese versions we do have to order in, but record labels often re-release popular albums 12-18 months after the initial release with a few bonus tracks. Then after five years or more if an album has been really successful it might get a re-release with a collection of extra tracks. There is often no rhyme or reason as to which albums get it, sometimes it's anniversary albums, some times it's tour albums, sometimes it just appears random, but the one thing it never is is predictable. I've got a few Australian tour EP's that were added to albums and I picked up Dark Angel's Leave Scars and Time Does Not Heal in "special" black covers with 5 or 6 live tracks on them from Amazon a few years back. I was a bit pissed off the live songs were songs already released on different EP's and compilations but I got the CD's to replace my LP's and the black covers are kind of cool.