Fluoride Action Network has made the voluminous 1992 Fluoridation Census accessible online with a search function.

VOLUME 1: CDC 1992 Fluoridation Census - OCR indexed
(55 mb PDF file; corrections from paper version included)
Population Served Fluoridated Drinking Water by Source System, Consecutive System, and County within State (as of 12/31/92)

• introduction with numerous informative tables, graphs and charts.
• A statistics page for each state with:
-- Number of Fluoridated Systems and the population receiving fluoridated water
-- Number of people receiving fluoridated and non-fluoridated water.
-- Number of Schools, Indian and Military Systems receiving fluoridated water
-- Identifies the number of systems using sodium fluoride, sodium silicofluoride and hydrofluosilicic acid
• Information on each state includes:
-- Name of community and water system
-- EPA ID Number
-- County
-- Chemical used
-- Status: "ADJ" = fluoridated; "NATL" = unfluoridated; "CONS" = receives water from a fluoridated system.
-- Fluoridation Start Date
-- Number of People Served
-- Natural Fluoride Level for non-fluoridated systems
-- Amount of fluoride added to water system = "OPT" level

VOLUME 2: CDC 1992 Fluoridation Census - OCR indexed
(11 mb PDF file; corrections from paper version included)
Communities Served Fluoridated Drinking Water, By County and Water System Within State (as of 12/31/92)
-- Information available by State:
-- Name of Community and County
-- Fluoridation Start Date:
-- Status acronyms:
"ADJ" = Fluoride added
"CONS" - Receives water from a fluoridated water system. Source system is identified.
"NATL" - Natural level

Full citation:

Fluoridation Census 1992

Published September 1993 by

U.S. Department of Health & Human Services
Public Health Service
Centers for Disease Control and Prevention
National Center for Prevention Services
Division of Oral Health
Atlanta, Georgia 30333