How do I export my playlist?

Hilight the playlist in iTunes' sources list and choose 'Export Playlist' from the file menu. Depending on the version of iTunes you may need to specify XML as the export format. Select that file with the 'browse...' button on the playlist entry form and press Submit. Depending on the size of your playlist, it may take several minutes. When it's finished, the next screen will say that the XML file has been uploaded and imported.