Gazetteers list geographical names and such and are much like maps but they also give historical and biographical info concerning the towns and early residents.
Online
For Clinton
Gazetteer and Directory of Clinton County, Iowa: containing a history of the county, directory of farmers and land owners, compiled by F. E. Owen, 1876. FHL film number 985421, item 9
Statewide
Hair, James T. Iowa State Gazetteer. Chicago: Bailey & Hair, 1865. FHL book 977.7 E4h; film 1024846 item 5 and film 982200 item 2; computer number 236479. This gazetteer contains some limited biographical information. There are also lists of occupations, the names of people employed in that occupation and the cities where these people lived.
R. L. Polk and Company. Iowa State Gazetteer and Business Directory. St. Paul, Minn.: Polk; A. C. Danser, 1882-1883. FHL film 989449 item 9 for 1882-1883 ed.: film 1007937 item 3 for 1884-1885 ed.: computer number 379001.
Ramsey, Guy Reed. Postmarked Iowa: A List of Discontinued and Renamed Post Offices. Crete, Neb.: J-B Publishing Co., 1976. FHL book 977.7 E5r; computer number 222715.
Mott, David C. Abandoned Towns, Villages and Post Offices of Iowa. Council Bluffs, Iowa: J. W. Hoffman and S. L. Purington Publishing, 1973. FHL book 977.7 E2m; film 973276 item 2 and film 967574 item 5; fiche 6051149; computer number 241550.