I want to visit China for business purposes, how can get a Visa to China?

You need to apply for a business visa to China, the fee is 50 Candian dollars for single entry visa,
you must provide one of the following documents if you want to get a business visa:

a. Authorized Invitation Letter for Visa Application issued by competent Chinese authorities (government or its foreign affairs and trade commissions) on both the national and provincial (provinces, municipalities and autonomous regions) levels (original or fax).

b. Authorized Invitation Letter for Visa Application issued by Chinese enterprises or public institutions duly authorized by competent Chinese authorities (original or fax) and both the original and photocopies of business license or business approval letter carrying the name of the applicant who has investment in or operates the business in China.

c. Invitation letter (original or fax) from a branch of the applicant's company in China.

d. Invitation letter/card (original or fax) from competent national authorities in China, local governments at township level or above, Chinese companies, enterprises or public institutions.

If you don't have one of the four letters, you can apply for a tourist visa to China, but you should write the purpose of coming to China is tourism.