Add this to .bashrc for "shamarok", which is an alias to the commandline DCOP interface to remotely drive Amarok.
alias shamarok="dcop --all-sessions --user $USER amarok player $1"
Works fine (for me!) without requiring a connection to the X11 server. Spacies machine is running as sweet jukebox, this is nice when shelled in ... other options of course are kbemused or Amarok Web Control ...