Quick install instructions:

su - root
cd /etc/yum.repos.d/
wget http://pkgrepo.linuxtech.net/el6/release/linuxtech.repo
yum install audacious

if you want to use Audacious with Pulseaudio (EL6 installs Pulseaudio by default) then also install:

yum install audacious-plugin-pulse

Audacious  has a lot of dependencies on libraries. As always I have only tested  this RPM with dependencies from the linuxtech repo. Mixing this  Audacious RPM with dependencies from other third party repos is  completely untested and might cause conflicts and errors.

How to make Audacious look like XMMS:
select: View > Interface > Winamp Classic Interface
after that: right click on the main window to open pop-up menu
then select: View > Interface Preferences...
select the 'Refugee' skin from the list and click on 'Close'