From Amarok Wiki
If you don't know how to add a repository, you might also have a look at the Kubuntu Community Help, there you can find a step-by-step guide on how to manage the Kubuntu repository list.
Stable version: Amarok 2.2
Kubuntu 9.10 the "Karmic Koala" will include Amarok 2.2 as its default Audio player!
Jaunty packages are not planned at the moment. You can use NEON if you wish.
To enable MP3 support, see MP3 on Kubuntu.