In the US when you buy an iphone do they give a sim also along?

Like on the apple website I saw that the price of the iphone is far less than in my country but then I got to know that you can only use it with some networks… But I have a way to get it factory unlocked… Coz there are like many ppl in my country who do such things… So now my problem is that I'm not going to the US I'm getting it from someone… Someone elce is getting it for me… So now as they say that it is bounded to some network so you also would have to give your details to get a sim… But he would be a outsider(like the person whose getting me the iphone fom the us) so can he buy it… What all details he needs to give and… What al to do?

Added (1). Okay so Hello, unknown friend and other ppl who gonna answer this question further.
First of all first point to unknown friend yes! Its true the iphone in my country costs 3times more than in the US for example: iphone 4s 16 gb in the US costs $99 which is equeal to Rs. 5, 5000 and in my country it costs for Rs. 35, 000 which is equal to $660 just the difference between these two phons is thathe iphone which I will buy from the US will only work with some networks (which only work in the US) which do not exist in my country (I heard the name of such networks for the first time… And this is my request to ppl wishing to hepl me know more about iphone… Actually I'm 17 yrs in 12th grade and I had said to my parents that if. I score good then they'll buy me a iphone! And that happned I scored good so now I'm entitiled to get a iphone but I'm thinking why to waste Rs.30000 when I'm getting the iphone in 5000 ican buy another phone of the saved money! So any1 wish

First off the iPhone is the same cost everywhere. Apple will not allow anyone to change that. The only way to get one at a lower cost is to sign up with a contract and pay the monthly fee. The carrier will pro rate the balance of the cost over the contract term making it appear less expensive. If you break the contract the balance is due immediately plus a cancellation fee.

Regarding which carriers let you use an iPhone it depends on the carrier, not all have the ability to support the iPhone and not all are 4g capable which is what the iPhone 5 is but you can change the iPhone to 3G if you wish. The iPhones older then the 5 are only 3G and because they are old models you may be able to buy a used one for less then the carrier charges or even get a new one free with a contract.

Once a phone is old and outdated the cost does go down. Apple does allow that just not for the current phones.

Regarding the sim chip, some companies will give you one as a promotion when they activate your phone on their network but most charge $10 to buy the sim chip needed to work on any network.

If you are buying it with a contract (on a GSM carrier of course) then yes it will.
If not, then no (includes factory unlocked models).