You can always do a country lookup from APNIC that will give you all of the IP's assigned to China (or any other country that regional registrar manages).

http://www.apnic.net/apnic-bin/ipv4-by-country.pl?country=CN

I wrote a script a while back that parses that list and creates an access-list for country blocking. Maybe I'll put it online one day.

At least that's how us network folk do it.