Playing mp3 files

Aparently I need some kind of plugin in order to play mp3 files with any of the standard players: noatun, Amarok, or XMMS. I did a google search and discovered a package, mpg123, that offers a standalone player. One of the posts mentions a library file, libmpg123.so, that supposedly can be gotten by compiling the mpg123 sources. I did get the standalone program but could not find the library file. I've also tried to find messages in this group on the subject with google but haven't gotten anywhere useful with that. How have people been getting through the mp3 thicket? Paul