I've been googling for a little while, and unfortunately, I can't find any solutions to properly sync a Zen with iTunes. Bummer, but it might not be possible. :/
Songbird is your friend. Very similar interface to iTunes, but with the Mozilla platform built in so you have a lot of extensions you can install into the program itself. Very nifty, and a quarter of the resources that iTunes takes up (it also works for the iPod).
[quote name='Karuto']Songbird is your friend. Very similar interface to iTunes, but with the Mozilla platform built in so you have a lot of extensions you can install into the program itself. Very nifty, and a quarter of the resources that iTunes takes up (it also works for the iPod).