I'm using Slackware 12.1.
I ran amarok (1.4.10). From the Tools menu I selected the Visualizations option. I received a pop-up error box that either libvisual is not installed or no plugins are installed.
Slackware 12.1 comes with the libvisual-0.4.0 package. Therefore the problem likely is a lack of plugins.
From slacky.eu I downloaded the build script for libvisual-plugins and installed the package. Then I started amarok and tried enabling Visualizations.
I received a pop-up dialog box filled with check boxes to choose a visualization plugin. I selected an option and the visualization effect worked just fine.
I would offer that amarok does not need to be recompiled after installing the libvisual plugins.
Are there other audio players with visualizations or did I just do a lot of work when there was an easier solution?
I think Kaffeine provides some visualization effects.