I wrote to the Chinese embassy in Kabul asking the following visa questions and they helpfully replied within 8 hours.
1. Can I obtain a 6 month visa in Kabul; and if not what is the maximum
length visa available?
Yes, you can get a maximum 6-month visa for tourism here, yet we need an introduction letter from your employer or organization.
2. What is the cost for this visa?
$60 for urgent(usually one working day), $30 for common(usually one week).
3. How long does the application take?
We receive applications from 9 to 11 in the morning during working days.
4. What are the requirements for obtaining this visa?
An introduction letter, a photo, an application form.
Happy with that...
Dan


Dan,
Ive just enetered china last month on a tourist visa. I managed to get a 6 month multimple entry but it measn i have to leave every 60 days. I wanted to change it so i dont have to leave. if you enter even on a one month tourist visa you can find organisations who hook you up with a class F business visa. I paid them 1600yuan and it takes about 10 days. its a little pricey but it was the only option i had. I am in shanghai though, not kabul. im sure you can find companies on teh net who will give you a letter if you wire them some money.
try
www.emoo.net or www.visainchina.com
both shanghai based but it could work.
I got my 6 month m.entery visa in bangkok without any invitation.
good luck