You could be applying for a visa either in your own country, within China or in a third country.  If you have any doubts about your situation you should enquire at a Chinese Consulate that issues visas or at a Public Security Bureau Entry and Exit Administration office in China.  China does not accept any postal or couriered applications from individuals.

China Visa Application in a Third Country & Regions
Travelers often need to obtain visas while en route, in another country, for example, you are austrians, you can also apply for a Chinese visa at China Embassy in Berlin, Germany. While it is possible to obtain visas in this situation it has become more difficult recently.  Some Chinese visa offices are refusing to issue visas to persons who are not resident in the country concerned.  In some cases having a visa for that country is considered OK, but this might be of no help if you are in a country where you do not require a visa.

There is no simple answer to this issue, nor is it clear exactly why this rule exists.  The first option is to try at every Chinese Consulate that you pass in the hope that one will grant a visa.  Another possibility is that if you can manage without your passport for a couple of weeks, you express mail or courier your passport and application to a friend or agent in your own country and have it sent back to you when the visa has been issued. 

Hong Kong and Macau are considered as foreign territory in respect to visas so they are 'third countries' in this context.   Hong Kong has traditionally been liberal in its application of visa regulations but this has changed since the Olympics.  However, those nationals who can most easily obtain visas in their home country should still be able to obtain them in Hong Kong, but maybe for lesser durations than was the case in the past.  The address in Hong Kong is

Visa Office of the Commissioner of the Ministry of Foreign Affairs of the People's Republic of China in Hong Kong SAR,
Address: 7th Floor, Lower Block, China Resources Building,
No.26, Harbor Road, Wanchai
Open 09:00 to noon, and 14:00 to 17:00, Mon to Fri (except Hong Kong public holidays)
Do not take large baggage as you are not allowed to take it inside.

Enquiry Service
Tel- Enquiry
24 hour Automatic Answering Telephone: 852-34132300
Live Answering Telephone: 852-34132424 (available at 10:00-11:00, 15:00-16:00 on workdays)
Fax: 852-34132312
Email: fmcovisa_hk@mfa.gov.cn
Website: http://www.fmcoprc.gov.hk/eng/

The Macau visa office is quite small and some travelers suggest is less generous than the Hong Kong office in the visas it issues. 
Address: No.992 Luo Li Ji Bo Shi Da Ma Lu (In Portuguese, the address is No. 992, Avenida do Dr. Rodrigo Rodrigues, Macao SAR, PRC)
Tel: (00853)87915126
Fax: (00853)87915102
Website: http://www.fmcoprc.gov.mo/eng/
Offices hours:
1. MON-FRI  9:00-12:00 a.m.      2:30-5:00 p.m.
2. 2:30-5:00 p.m., FRIDAY is open only for Pick-up.
3. Office is closed on Sat, Sun & Macau Public Holidays.

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