Alaska Department of Natural Resources Public Information Center:  Use this site to access DNR information on all kinds of maps, plats and other data specific to the State of Alaska.   http://dnr.alaska.gov/commis/pic/maps.htm 

USGS Historical Topographic Map Explorer:  Use this site to access historical topographic map information anywhere in the United States.    
http://historicalmaps.arcgis.com/usgs/ 

USDA Web Soil Survey:  Web Soil Survey provides soil data and information produced by the National Cooperative Soil Survey.  
http://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm