Unless you are a Japanese, Singaporean, Brunei, or Chinese citizen, you will definitely have to get a visa. I recently went to China, and also live pretty far away from the nearest consulate in Osaka. Unfortunately, Chinese consulates do not accept visa applications by mail, so you have two options:
1. Go to the nearest consulate and apply in person, wait until the end of the processing period, and pick up the visa in person. The normal processing period is four days, but you can pay an extra 3000 yen to have it expedited to the following day. Because the consulates are only open on non-holiday weekdays (and visa applications are only accepted from 9 AM to noon at least in Osaka), this will probably require nenkyu or daikyu. Also, there is a chance that no one at the consulate will speak English; when I contacted the Osaka consulate, I had to speak in Japanese.
2. Have a travel company arrange the visa for you. I used the travel company from which I bought my plane ticket to China, and they charged about 10,000 yen for the visa service. They provided the forms I needed and advised me on how to fill them out.
In the end, although it's a little expensive, I would recommend the travel company option, because it still probably costs less that a trip to the consulate and overnight stay.
Also, don't wait to submit the form and make sure that you've dotted all your i's and crossed all your t's. My first form was rejected because it was on two separate pages rather than a single page front and back, and because the photo I attached did not fit exactly within the allotted area. By the time I got a new form to them, the application had changed, and so my second form was rejected as well. Although I had applied with two months to spare, these delays combined with the fact that all of these papers had to be mailed through the travel company meant that I didn't get my visa until four days before I was scheduled to leave for China. Also, if you're planning on going to Hong Kong and then re-entering mainland China, be sure to apply for the double-entry visa.
I hope that this helps! I had a very difficult time finding information about this subject. The whole process was completely different from applying for a Japanese visa or coming to Japan on a tourist visa.