United States Department of Agriculture - Rural Development (USDA-RD) Offices
Chapter 4 of Homes Buyers and Mortgages covers the key aspects for loan approval (do you qualify income wise and does the property qualify). This chapter also explains the two loan programs offered by the USDA-RD (Direct or Guaranteed) and which of them is right for you. As always, make sure you have the right team of professionals in your corner (lending and real estate).
The link (click any state) provided puts you in touch with the state office for the USDA-RD. Ask them for the contact information for your nearest USDA-RD office.