I have a question about ordering the iphone from the apple store. please help.?

I'm an at&t customer. I'm due for an update in august however my phone was being kind of stupid and my dad let me use his update to get a new phone. I just ordered the iphone 3g s online, but I still have some questions, I would really appreciate it if you guys could answer those for me. Thanks :] 1. Does the iphone come with a new sim card when you order it from the apple store? 2. If not, can i use the same sim card that i have now from my blackberry? 3. when purchasing the iphone online, apple asks for a phone number. Is that to check if you qualify for an update? 4. And when they ask for that number and you buy a $30 service plan for the iphone, that's not connected to the number at all is it? I mean that plan is for the phone, not the number right? 5. So basically, even though i used my dad's update to buy the phone, I can activate it so that it's my phone? Sorry for the seemingly stupid questions but i just want to be sure. Thanks so much for taking the time to read and answer this :]