The Susan Glaspell Society
http://academic.shu.edu/glaspell/
A society devoted to the performance and study of Susan Glaspell's plays and novels. Link includes information about Glaspell and a bibliography of primary and secondary sources.
Susan Glaspell--Trifles
http://itech.fgcu.edu/faculty/wohlpart/alra/glaspell.htm
The text of Trifles, as well as some background information of the play, from the University of South Florida.
Provincetown Playhouse
http://www.provincetownplayhouse.com/
Information about the Provincetown Players, an influential group of writers and actors co-founded by Glaspell.