You can't get any version of the Justkaraoke because the developers are not in the business anymore. The official website (previously known as Tricerasoft) displays a page with some links to bogus search results which I wouldn't recommend clicking.
I suggest getting other applications that are as good as JustKaraoke. For example, there is PowerKaraoke. They have all kind of applications to create, burn, play, and organize your Karaoke files.