For entry into China, non-Chinese citizens should apply for a visa at the Chinese Embassy or Consulate in the region they live. Obtaining a visa for entry into China is not difficult, but it is important to allow enough time for processing your application. There are the following two types of visa you may consider for your travel: 

• Visa F: Issued to an applicant who is invited to China on a visit, on a study or lecture, business tour, for scientific-technological and cultural exchanges, for short-term refresher course or for job-training, for a period of no more than six months. To apply for a Visa F, the invitation letter from the inviting unit or the visa notification letter/telegram from the authorized unit is required.
• Visa L: Issued to aliens who come to China for sightseeing, visiting relatives or other private purposes. For a tourist applicant, in principle he shall evidence his financial capability of covering the travelling expenses in China, and when necessary, provide the air, train or ship tickets to the heading country/region after leaving China. For the applicants who come to China to visit relatives, some are required to provide invitation letters from their relatives in China.

You can use http://www.fmprc.gov.cn/eng/wjb/zwjg/2490/ to find the local Chinese Embassy web and get detailed information. Taking US an example, the detailed information about visa procedure, forms, and questions is located at http://www.china-embassy.org/eng/ywzn/lsyw/vpna/