I live in China just built a PC using GTX460 SLI, had some power supply issues
http://www.tomshardware.com/forum/forum2.php?config=tomshardwareus.inc&cat=33&post=295143&page=1&p=1&sondage=0&owntopic=1&trash=0&trash_post=0&print=0&numreponse=0"e_only=0&new=0&nojs=0
I paid 1470RMB for one 1gb 460 card, in a town called Shajing, technically part of Shenzhen City.
Its the Galaxy card, factory overclocked to 700mhzGPU.
Galaxy is a company formed Shenzhen, so its actually a Chinese brand.
My card works beautifully, paired with a i7930, and the overclocking software it comes with is really easy to use and powerful.
Depending on where your friend is going will depend on the price he pays.
For instance if you go to a famous or large computer marekt, the starting price will be higher, as the rents are higher.
I went to a famous one in Shenzhen down town and they wanted 1700RMB for the same card, I could haggle them down to the same 1470RMB, then then that market is far from my home.
There are no export taxes or import taxes, and even if there are you would be a muppet for declaring these things anyway.
As far as warranty goes, i am not sure, but i should imagine that as long as you register the card with their site or something like that then it will be fine. Also international shipping isnt that expensive if it comes to it, $20 for the first 500g Shenzhen to USA.
Taobao is not to be trusted, everything is faked in CHina, and that is not an understatement, there is obviously real stuff on there, but just as much fake crap as well, be aware.
However if anyone has had good experinces from it i would love to hear as its often the cheapest place to shop for PC stuff, in China.