If you are referring to Chinese Stocks listed on U.S. exchanges than nearly any broker-dealer should be able to assist you. Some of the larger brokerage firms however may have compliance issues with some of the stocks you are looking at, for instance if the share price is under $5 or the company is not currently listed on a senior exchange (i.e. Nasdaq, NYSE, etc.) However, smaller brokerage houses often are able to buy whatever stocks they want. Many of the Chinese stocks listed on U.S. Exchanges can even be bought through an online trading platform such as: Scottrade, Charles Schwab, E*Trade, Fidelity, the list goes on and on.
If you are looking for some investing ideas related to Chinese Stocks here is a viable site: http://www.redchip.com/visibility/sectors.asp?sector=china