Once you have all your music on the iPod you just need to know how to transfer ipod music to computer to be able to enjoy your favorite tunes on either device. To be able to perform this task you will simply need to authorize the computer that you want to use to back up the music files. This is a relatively simple process. Open iTunes on the computer you wish to authorize. Find the “store” tab in the menu and then choose the option to “authorize computer.” You will then be asked for your Apple ID or you AOL log in information depending on the way you typically log in to iTunes. After you are logged in, select “authorize.” Then iTunes and the Apple Store will recognize the computer as valid and you can transfer files between the two.
Using your USB cable, connect the iPod to the now authorized computer. When the menu comes up select the “transfer purchases” option. If it does not automatically offer you this option just select “transfer purchases from (iPod name)” from the menu under the file tab. It should take only a few minutes for iTunes to transfer your purchased music from the iPod to the computer.