Successfully managing a business requires specific management skills in addition to knowledge of key practices. A business is an ongoing activity that doesn't run itself. As the manager, you will have to set goals, determine how to reach those goals and make all the necessary decisions. You will have to purchase or make your product, price it, advertise it and sell it. You will have to keep records, and determine costs. You will have to control inventory, make the right buying decisions and keep costs down. You will have to hire, train and motivate employees now or as you grow.
Marketing
http://marketing.about.com/od/marketingbasics/a/smmktgbasics.htm
http://www.bplans.com/sample_marketing_plans/
http://www.mplans.com/sample_marketing_plans/
Human Resources/Personnel
http://www.mplans.com/sample_marketing_plans/
Finances
http://www.businessfinance.com/
http://www.allbusiness.com/accounting/2984839-1.html
Technology
http://www.allbusiness.com/electronics/computer-equipment-laptop-computers/4968505-1.html
Other operations
http://www.allbusiness.com/operations/2985109-1.html