"Not at all. You just pop the sim card out of the slot in the top of the
iPhone. The only thing you need is a paper clip. It's designed to be
swapped." - Ben Gracewood
"...or just take the sim out of their existing phone (which the iPhone is
naturally usurping) and stick it in the iPhone?
Or grap a pre-pay sim.
Or yes just go and start a new account with a sim by itself.
No activation required. Any sim will do." - Ben Gracewood