These three major government publishers all produce free catalogs advertising the latest titles. (Most of the publications, however, are not free.)

1. Government Printing Office (GPO) sells over 44 million books each year and keeps 21,000 titles in stock. Get on their mailing list to receive the monthly catalog by calling or writing:

GPO--Superintendent of Documents, Washington, D.C. 20402; 202-783-3238.

2. National Technical Information Service (NTIS) sells over 6 million books annually and maintains approximately 80,000 titles in stock. A free catalog (#PR 154) is available by contacting:

NTIS, 5285 Port Royal Rd., Springfield, Va. 22161; 703-487-4600.

3. Consumer Information Center offers roughly 25,000 publications each year. About half cost you nothing. A free catalog is available by writing:

Consumer Information Catalog, Pueblo, Colo. 81009.

Among the many federal agencies from which you may request free catalogs or a publications list:

1. Consumer Product Safety Commission (CPSC) Catalog, Washington, D.C. 20207; includes fact sheets, pamphlets and audiovisual materials available.

2. Federal Reserve Board, Publications Service, Room MP-510, Washington, D.C. 20551; list of reports and consumer materials.

3. General Accounting Office, Publications Office, 441 G St. NW, Washington, D.C. 20548; monthly catalog of latest reports which usually rate effectiveness of various government programs.

4. Geological Survey, National Cartographic Information Center, 507 National Center, Reston, Va. 22092; catalog of maps, aerial photographs and other cartographic data available.

5. GPO Bibliographies, Superintendent of Documents, Washington, D.C. 20402; free list of 250 bibliographies that identify all GPO books for a specific subject (i.e., Business and Business Management, Cookbooks and Recipes, Poetry and Literature).

6. National Institutes of Health, Publications List, Office of Communications, Editorial Operations Branch, Bethesda, Md. 20205; catalog provides list of publications of all the National Institutes.

7. National Ocean Survey, U.S. Dept. of Commerce, Washington Science Center Room 103, C5, Rockville, Md. 20852; catalog of nautical charts, historical and nontechnical publications (i.e., shipwrecks).

8. Office of Technology Assessment, U.S. Congress, Washington, D.C. 20510; OTA's list of publications includes their analytical studies on energy, national defense, health and life sciences.

9. Small Business Administration, P.O. Box 15434, Forth Worth, Tex. 76119; Toll-free: 800-433-7212; list of free SBA publications (#115A) as well as separate list(#115B) which includes those for sale.

10. Smithsonian Institution Press, Distribution Center, P.O. Box 1579, Washington, D.C. 20013; catalog of books and studies related to the arts, science, technology, history, air and space.

Besides publications, 175 federal agencies produce films, slide sets, audiotapes, and multimedia kits on a wide range of subjects. For a free catalog, request the reference list of audiovisual materials from:

National Audiovisual Center, General Services Administration, Washington, D.C. 20409.

In case you're curious about which publications are the government's best-sellers, send a stamped, self-addressed envelope to:

Information USA, Dept. GBS, 1000 Connecticut Ave. NW #9, Washington, D.C. 20036.

Shop around. There is bound to be something written about almost anything you want to learn more about.