Work visa:

Apply for a work visa at the Turkish embassy or consulate at least two months prior to your departure. Your employer should send certain documents to the Turkish Ministry of Labour and Social Security at the same time.
The Ministry of Labour and the Social Security will process your application within 90 days.
Once your application has been approved, so then you have to pay the work permit and work visa processing fees. You are not allowed to begin work until you have obtained all 3 of the required permits.

Business visas:

Business visas are almost similar to tourist visas but are issued to travelers visiting Turkey on temporary business. Business visas are generally issued for up to 90 days and are valid for a single entry. If you need a business visa and you want to enter Turkey, So have to proof your business in Turkey. Your employer/employers should be able to provide you with an appropriate letter or document.

Read More at http://www.visaworker.com/turkey/