In order to use Amarok with esound (the "Enlightened Sound Demon" (esd)), you must install the package "libxine1-gnome" (that's the name on Ubuntu). Afterwards you will be able to choose the "esd" as output module in "Settings > Configure Amarok > Audio-output".
For more information about Amarok and different audio engines, see:
http://wiki.ubuntuusers.de/Amarok
Amarok & ESD
Amarok & ESD
Jumping out of an airplane is not a basic instinct. Neither is breathing underwater. But put the two together and you're traveling through space!