How does the iphone upgrade process work?

I have an iphone 3g, and checked my upgrade eligibility. It said that I qualified for a two year contract + 36 dollars to get the new iphone 4S. My question is does this really mean that I can trade in my iPhone 3g to get an iPhone 4S for just 36 dollars, or does it mean that I just renew my contract for that price? Do I still have to pay the $199 for the iPhone 4S, or do I just trade in my iphone 3G?

How to stop purchased songs from syncing to a iPhone?

I purchased some song from the iTunes store on my iPhone and I can't get rid of them.
I've unclicked all of the automatic download/sync options on both my iPhone and iTunes, and even when I delete them from my iPhone they automatically restore themselves, I even have 'Sync only ticked songs and videos' clicked on my iTunes but these albums still get back onto my iPhone -.-
How do I get rid of them for good?

What color iphone should i get? - 1

So i'm getting my first iphone on Thursday and i'm not sure if i want black or white. I'm kind of leaning towards white. I've heard that more girls get white and guys get black. What color do you think i should get. I'm a girl by the way

Can you use a prepaid Sim Card in an iPhone?

Okay I have an iPhone 4, currently I have internet and unlimited text with At&t, however due to family issues, our service is getting cancelled and mom has agreed to buy me a prepaid phone from At&t, with unlimited text and 250 minutes for $25.So I'm wondering if I cut my prepaid Sim card and put it into my iPhone would it still work? If I activate the Sim and then just slip it into the phone. Without a Data Plan? Or will At&t add a Data plan on there automatically?

Can iphone 4 be for at&t prepaid?

My little sister has prepaid at&t phone, she is getting the iphone4. But sense the sim cards are smaller for the iphone4 than any other phone how would she fix the problem? Could we go to at&t to get a new sim card?