books.google.com - Contains extensive data about population in all of the states and counties of the U.S. from 1790-1990. Contents: population of the U.S. and each state; population of counties, earliest census to 1990; and historical dates and Federal information processing standard (FIPS) codes. Information presented...http://books.google.com/books/about/Population_of_States_Counties_of_the_Uni.html?id=Z12v1lrkv2IC&utm_source=gb-gplus-sharePopulation of States & Counties of the United States: 1790-1990
