Personally I hate the term American, as America is a continent from which the US is part of, but that is a PRSI subject and a different topic

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I am not sure what you mean by most of the world, however looking at Orange in the UK, shows the 4S available for £49.99 , and two available cost plans form which the phone is free.
http://shop.orange.co.uk/mobile-phones/iPhone-4s-8GB-black
T-Mobile in Germany also offers a low cost / subsidized version of the 4s from what I gather as well.
http://www.t-mobile.de/shop/handy/0,4855,2963-_304597-0-1-0,00.html
The only reason I am aware of those options, is due to the fact of my being on those sites for a planned European trip, looking for a completely different product, a prepaid sim for my iPhone 4.
That said, I understand subsidized phones outside the US is more often rare than where I live.