Key online sources:
Industrial Workers of the World official website is a rich source for historical as well as contemporary information.
The Industrial Worker and Industrial Union Bulletin digitized by Marty Goodman of the Riazanov Library Project and made available at Marxists.org.
Chronology of IWW History , by Michael Hargus, Industrial Workers of the World website
Paul F. Brissenden, The I. W. W.: A Study of American Syndicalism (1919)
Robert L Tyler, Rebels in the Woods: The IWW in the Pacific Northwest (1967)
Primary sources online:
1912 IWW Convention Proceedings --digital copy from Hathi Trust
1916 IWW Convention Proceedings -- digital copy from Hathi Trust
1919 IWW Convention Proceedings -- Hathi Trust
IWW Pamphlets & Other Literature--digital copies of several dozen pamphlets on Jim Crutchfield's IWW Page
Michigan State University Library Digital Collections: IWW--digital copies of a dozen important documents
University of Pennsylvania Industrial Workers of the World History -- digital copies of many books and pamphlets
Wm. Haywood, "With Drops of Blood. The history of the Industrial Workers of the World has been written" (1919)
Vincent St. John, The I.W.W.--Its History, Structure and Method, (1917)
Online exhibits/projects:
The Legacy of Joe Hill --this comprehensive site explores the murder trial and aftermath of Joe Hill's 1915 execution