If the music is still stored on your iPod, you can sync the device with your computer by connecting the iPod to the computer's USB port. Once connected, you will need to open iTunes and begin the sync process. Since there are no songs on your computer, the sync should copy everything from your iPod over to the computer.
If this does not work, try clicking File and then selecting "Transfer Purchases From name_of_your_iPod". This will force a sync of all the songs, movies, books, etc.
Darius Cubbage / Technical Support Analyst / Hosting.com