It can be hard. Generally AT&T will ask you to sign up a 2-year contract.
But you can buy it from other sources and unlock it to use in China.
I personally do not think it is worth it since, without the service from AT&T, it is just a very expensive iTouch. And you will lost the warranty by unlocking it.
Also, just FYI on the new 3G iPhone.
"Two new models of iPhones go on sale July 11 for $199 and $299, depending on the amount of memory, with two-year AT&T contracts. The no-contract versions will cost $599 and $699 and will be sold sometime "in the future," AT&T said. Buyers would then go month-to-month on AT&T's service. AT&T said the no-contract phones would be "locked" to work only on AT&T's network, as the contract-laden phones will be."
But you can buy it from other sources and unlock it to use in China.
I personally do not think it is worth it since, without the service from AT&T, it is just a very expensive iTouch. And you will lost the warranty by unlocking it.
Also, just FYI on the new 3G iPhone.
"Two new models of iPhones go on sale July 11 for $199 and $299, depending on the amount of memory, with two-year AT&T contracts. The no-contract versions will cost $599 and $699 and will be sold sometime "in the future," AT&T said. Buyers would then go month-to-month on AT&T's service. AT&T said the no-contract phones would be "locked" to work only on AT&T's network, as the contract-laden phones will be."