How to transfer music to my iPod (& iTunes) {click on link}.
Simple technique of Drag & drop the audio file onto the Library icon of iTunes to add to iTunes.
I 'highly' recommend Manual updating of the iPod's playlists.
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That means you can add songs as you desire, not need to re-do any playlist for the iPod (unless of course that's what you prefer, as otherwise the iPod deletes the previous playlist on the iPod.)