The Newberry Library
http://www.newberry.org/collections/Railroad.html
The Newberry Library houses several prominent railroad collections, including the Pullman Company Archive. The finding aid for the Pullman Collection is here:
http://www.newberry.org/collections/PullmanGuide.pdf. The collection is wide reaching and contains materials related to the town of Pullman, the Pullman Strike of 1894, Mexican and British operations, Pullman cars, employees, labor relations, and unions, as well as many other topics.

The Encyclopedia of Chicago
http://www.encyclopedia.chicagohistory.org/
The Encyclopedia of Chicago is a dynamic online resource for metropolitan history.
Thousands of resources—including articles, photos, maps, broadsides and newspapers—related to Chicago’s history are available. The online encyclopedia contains multiple entries related to Pullman and other Chicago neighborhoods. (Just type “Pullman” into the search box to begin.)

The Historic Pullman Foundation
http://www.pullmanil.org/
The Historic Pullman Foundation Web site provides a history of the town as well as a larger historical context of the district. The site has excellent links and bibliographies for further research.

The Pullman State Historic Site
http://www.pullman-museum.org/
The Pullman State Historic Site Web site includes digitized primary sources such as photos and newspaper clippings. Here, you also will find transcribed interviews with Pullman workers and in-depth coverage of specific topics related to Pullman, including “Politics and Pullman” and “Pullman and the Spanish Flu Epidemic.” The site highlights labor and race relations as well as the town and the company.

The A. Philip Randolph Pullman Porter Museum
http://www.aphiliprandolphmuseum.com/
The A. Philip Randolph Pullman Porter Museum site provides general information and history about the Brotherhood of the Sleeping Car Porters as well as a list of useful links for labor, African-American, and railroad history.

The Dramas of Haymarket
http://www.chicagohistory.org/dramas/overview/over.htm
The Dramas of Haymarket is an online project produced by the Chicago History Museum and Northwestern University. The Dramas of Haymarket examines selected materials from the Chicago Historical Museum’s Haymarket Affair Digital Collection, an electronic archive of CHM’s extraordinary Haymarket holdings. The site interprets these materials and places them in historical context.

The Great Chicago Fire and Web of Memory
http://www.chicagohs.org/fire/
The Great Chicago Fire and Web of Memory is an online exhibition created by the Chicago Historical Museum and Northwestern University. The site includes digitized primary sources focusing on Chicago during the second half of the nineteenth century.
Sources include photographs, documents, and pamphlets as well as essays written by historians placing the primary sources within historical context.

This Library of Congress Collection
http://memory.loc.gov/ammem/award98/ichihtml/hayhome.html
This Library of Congress Collection showcases more than 3,800 images of original manuscripts, broadsides, photographs, prints, and artifacts relating to the Haymarket Affair in the collections of the Library of Congress.

Illinois During the Gilded Age
http://dig.lib.niu.edu/gildedage/
Illinois During the Gilded Age, a project of Northern Illinois University, provides primary and secondary material about Illinois between 1866 and 1896. The site houses multimedia material such as videos and recorded sound as well as digitized documents and photographs.
The site contains a section specifically dedicated to the Pullman Strike here:

The Labor Trail
http://www.labortrail.org/
A joint project between the Newberry Library and the University of Illinois at Chicago's Department of History, and the Chicago Center on Working Class Studies, funded by the Illinois Humanities Council.
This on-line history resource builds on “The Labor Trail: Chicago's History of Working-Class Life and Struggle,” a map of 140 significant locations in the history of labor, migration, and working-class culture in Chicago and Illinois.

Illinois Labor History Society
http://www.illinoislaborhistory.org/
The purpose of the Illinois Labor History Society to encourage the preservation and study of labor history materials of the Illinois Region, and to arouse public interest in the profound significance of the past to the present.

The Black Metropolis Research Consortium
http://www.blackmetropolisresearch.org/
The Black Metropolis Research Consortium (BMRC) is an unincorporated Chicago-based association of libraries, universities, and other archival institutions with major holdings of materials that document African American and African diasporic culture, history, and politics, with a specific focus on materials
relating to Chicago. The University of Chicago serves as the host institution for the BMRC.

The Chicago History Museum
http://chicagohs.org/
The Chicago History Museum is the repository for the records of the Brotherhood of Sleeping Car Porters as well as George M. Pullman's personal papers. In addition to these core collections, the Chicago History Museum also has a number of ephermeral items related to the Pullman town and community, including most of the few remaining photographs taken during the 1894 strike.