When ordering an iPhone 5S from apple online?

I'm going to buy the iPhone 5S soon, but I'm not sure whether or not to buy it in-store or online. The reason I'm not sure is because I don't want the employees of the apple store to unbox the phone for me, I want to enjoy the unboxing experience on my own. If you order online, does the iPhone come with the SIM card (I have not owned an iPhone before and I'm an AT&T customer). Also, how does the SIM card come programmed to be your cell phone number or does this have to be done at a certified AT&T retail store?

The SIM card comes preloaded in the phone if you order it online. In the store ask them not to take it out of the box.

All you need to do is ask. Just tell them not to open the box, that's all.