wordTube is your Media Center plugin for WordPress.
Upload the files to wp-content/plugins/wordtube
Go to the web page http://www.longtailvideo.com and download the JW FLV Media Player 5.0 or higher and unpack the content
Upload the file player.swf and yt.swf to the WordPress upload folder
Activate the plugin
Upload a .flv video file or an mp3 sound file to the WordPress upload folder or use the Upload form at Manage -> wordTube
Optional you can upload a image to show a preview of the video/mp3 file
Go to your post and enter tag [media id="media id"] or [playlist id="playlist id"].
That's it ... Have fun