If you have windows xp and media player 10 it easy. Just open media player, plugin your ilo. Next in media player you will see a drop down arrow by "now playing", click on the arrow and set it to sync list. Now just drag and drop any songs from the library list on to the sync list and then click on the sync button at the bottom of the sync frame.

Also with the ilo connected you can explore your computer and open it up like any other drive. Then you can drag and drop any song into the music folder or cut and paste.

Important note: You will not be able to see the music files on the player if they are within a file using either method. To fix this explore the ilo as in the 2nd method and cut and paste all songs out of their files and drop them on the root directory "music". Now all song will appear.

To find your song in an organize way, use the menu button on the ilo and look them up under "artist".

Hope this helps