Catalog of Federal Domestic Assistance
The Catalog of Federal Domestic Assistance, the place to start when looking for information about federal loans and grants.
http://www.gsa.gov/fdac

Foundation Center
Foundation Center offers users the chance to search for foundations by name, state, and zip code free of charge. Further searching is available at a fee.
http://foundationcenter.org

grants.gov
Grants.gov is the starting point for organizations seeking to apply for federal grant funds. Learn about upcoming grant opportunities, how to apply, and how to monitor the progress of your application.
http://www.grants.gov/

Missouri Catalog of State Assistance Programs: A Listing of Grants, Loans, and Assistance Programs
The Catalog offers information about Missouri state government funds that are available to Missouri “non-profit agencies, state and local governments and private companies.” The directory has brief information about eligibility, and details about which agencies to contact.
http://www.business.mo.gov/pdf/MoCSAP.pdf