County City Data Book (2007)
The most comprehensive source of information about the individual counties and cities in the United States. It includes data for all U.S. states, counties, and cities with a population of 25,000 or more. It contains additional data for places with a population of 100,000 or more. Also included is a complete set of state maps showing all counties, places of 25,000 or more population, and metropolitan areas.