Here is a guide to install the latest version (version 3.0-1) of Audacious on Ubuntu 11.10. You can install Audacious using the Ferramosca Roberto PPA for Audacious.
To add the PPA and install Audacious open a terminal window (press Ctrl+Alt+T) and copy+paste the following lines:
sudo add-apt-repository ppa:ferramroberto/audacious
sudo apt-get update
sudo apt-get install audacious
Suggested packages: libmcs-backend-gconf libmcs-utils
sudo apt-get install libmcs-backend-gconf libmcs-utils
When Audacious is installed close the terminal window and to start Audacious press the SuperKey and type: audacious
Audacious is an open source audio player. A descendant of XMMS, Audacious plays your music how you want it, without stealing away your computer’s resources from other tasks. Drag and drop folders and individual song files, search for artists and albums in your entire music library, or create and edit your own custom playlists. Listen to CD’s or stream music from the Internet.