Continuum Shift Extend is a retail release, so yes it will be a new disc. I notice that your location is Norway, so I can't really speak for you in terms of international release, but if you want to import it, expect to pay anywhere from $75-$90 USD shipped, it released in Japan on December 17th. Otherwise, you can wait for the English version to come out in North America on February 14th. The "Japanese" and "Asia" versions are two different regioned versions of the game, the only difference as far as I know is that the Asia version comes with English menus, while the Japanese won't doesn't. So if you plan to import, go for the Asia one, which also happens to be cheaper. PS3s are region free so theres no need to change your region, the console will play games from anywhere in the world.
Hope that helps