How do I setup the landline computer portion of iTunes so I can then download apps?

I work in Chat at Apple dealing with this question all the time. I am not %100 sure what you are referring to “setting up landline portion of iTunes” So this answer my not be what you are looking for, but here goes.

1. Your “landline” computer, which I am assuming is your computer at home, or your main computer, needs to have iTunes installed on it. (Your iTunes account on your computer is what controls everything “iPod”.) So download iTunes on your computer. You can find that at apple.com/downloads/

2. Second you will need to sync your iPod touch/iPhone, I am assuming you have an iPod touch. Either way it is the same process. You need to connect your iPod/iPhone to your computer and make sure to sync it with your iTunes account on your computer. If your iPod/iPhone is not synced with your iTunes account information on your computer how, is it suppose to know what account to bill? Sure you may be downloading all the free Apps. But it all has to be linked to YOUR account.

I hope this helps out. If not it is always best to get in contact with iTunes support. They will also be able to help you out.