Copy the music over to the computer you wish to play it on, and import it into iTunes. When you try to play the file, you will be prompted to enter the password for the account used to download the song. Once complete, the computer will be authorised.
Remember, you can only authorise a maximum of 5 computers.
itunes
You access itunes on your computer by opening up the file to where you've downloaded itunes to. You open the browser to where itunes has been saved and will restart your computer once you've clicked on it in order to add itunes onto your desktop.
you can put it on a memory stick
plug it in your computer
iTunes for the computer is very different than the iTunes that you have on your iPod Touch. You can only have the iTunes from your computer when you download it for your PC (not for the Mac, there are two separate iTunes softwares) from Apple's website.
If you have iTunes program installed on your computer and the computer is connected to the Internet then you have all you need
you can og into your itunes account from the other computer
When you buy an iPod you need to have a computer - authorise - the iPod to it. For some reason the machine has forgotten where it is supposed to be. Check what machines are authorised to your computer. At worst you will need to de-authorise all iPods on your computer and start all over again. If the problem persists then take the machine to your nearest Apple Store.
Your iTunes balance is saved server side. Long story short, as long as you log in with the same account on the other computer's itunes client, then yes.
Yes - go to http://www.apple.com/itunes.
activate the phone first and then sync it with your itunes on your computer
Sync your iPhone to iTunes on our computer