I need to know all about the iphone, not about the features but about how much you have to pay and if you can change the company, and if I already have my music saved on my computer can I just add it on? I don't get any of this itunes stuff, so please help.
Also if I change to any other company how much will they charge me?
How much does AT&T charge overall?
I read something about voice plan? What is that?
And for AT&T which do I choose for "How to purchase"
(It says something about if your company pays for it, if you pay it or if you are a small business owner) What does all of that mean?

Also for AT&T what does it mean to be upgrade eligible?
What other expenses are there?