Unfortunately, the automatic backups made by iTunes will not have included your actual media content -- only things like settings and application data are backed up.
When setting up the new iPod touch, iTunes should prompt you to restore from your old backup, assuming you're using the same computer and iTunes library. Again, however, this is only going to give you settings, application data, and camera roll photos; iTunes expects the other media content to be in your library, so although it will restore your sync settings (e.g. what playlists you had selected), it won't be able to put the actual content back on unless it was in your library to begin with.
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