I have to say that the windows media player is very nice and it have many features for the music storage. Personally I like the way windows media player manages the music, so I look for a alternative for linux with that features and I find amarok.
Amarok is developed for the KDE desktop environment even though amarok also is able to run under the GNOME desktop environment.
This is the package description:
Amarok tries to be a little different, providing a simple drag and drop
interface that really makes playlist handling easy.
- rapid playlist creation, with drag and drop from a directory view
- context information (lyrics, artist information, similiar tracks/artists)
- nice playlist browser for your existing playlists (PLS or M3U formats)
- collection-indexing support, for smart browsing and playlist creation
- inline ID3 tag editing, capable of retrieving tags via MusicBrainz
- album cover support: automatically displays album covers from the
filesystem, or downloaded on the fly
- miscellaneous audio effects, including crossfading
- easy bindable global shortcuts, rich DCOP interface
- On-Screen Display (OSD), fully configurable
- iPod and iRiver support
Support for XMMS and libvisual visualization plugins is also compiled in (you
need to have xmms or libvisual0.4-plugins installed to be able to use it).
No doubt amarok is a excellent alternative for windows media player.