A-Z Index of U.S. Government Departments and Agencies (USA.gov)

LSU Libraries Federal Agencies Directory

toll free telephone numbers:

1 (800) FED INFO = 1 (800) 333-4636 to call the National Contact Center toll free 8am-8pm, Eastern time, Monday-Friday

Federal Toll-Free Telephone Numbers

on paper:

U.S. Government Manual (1997 - current is available online from GPO Access)
available in Meriam Library : ref JK 421 A3 and doc AE 2.108/2:

other:

Agency Index ( Washburn University, School of Law)
(includes links to : Agency Home Pages, Publications, Organizational Charts, Forms, Opinions/Actions, Manuals, Libraries, Directories)

FAQs by Agency and Program (USA.gov)

The Federal Web Locator (Villanova Center for Information Law and Policy)

info.gov

see also: Meriam Library -- Government Portals