These are some of my favorite and frequently used links:

Research and Preservation

Jackson Hole Historical Society and Museum
https://jacksonholehistory.org/

Wyoming State Historic Preservation Office
http://wyoshpo.state.wy.us/

Planning and Historic Context Development Program, Wyoming SHPO
http://wyoshpo.state.wy.us/HC/Index.aspx

Wyoming State Archives
http://wyoarchives.state.wy.us/
 
American Heritage Center, University of Wyoming
http://ahc.uwyo.edu/usearchives/default.htm
 
Wyoming Libraries Database
http://wyld.state.wy.us/
 
Wyoming State Historical Society
http://wyshs.org/
 
Land Patent Search, Bureau of Land Management
http://www.glorecords.blm.gov/
  
National Park Service Route 66 Corridor Preservation Program
http://www.nps.gov/rt66/

Oklahoma State Historic Preservation Office
http://www.okhistory.org/shpo/shpom.htm?full

Historic Santa Fe Foundation
http://www.historicsantafe.org/