If one particularly interests you I'm sure you could contact the owner and explain your predicament and they'll be able to send it over.
A slightly more expensive way which might work is like @Mipey's idea: rent the cheapest US server you can find. They should give you a Remote Desktop account to log in to. Now you can surf the internet from the US server, and unless your specific server is blocked you've got the internet as it is seen from the US (most countries have *some* form of blocking at the ISP level, but DropBox is definitely allowed!)
Disclaimer: I don't know Chinese law and if this is the type of thing that could get you in to trouble, I cannot officially recommend that you do it. :P