Directors Guild of Great Britain was created in 1983.
Showmen's Guild of Great Britain was created in 1889.
Little Theatre Guild of Great Britain was created on 1946-05-18.
Guild of Food Writers was created in 1984.
Writers' Guild of Norway was created in 1938.
Australian Writers' Guild was created in 1961.
Screen Writers Guild was created in 1933.
British Guild of Travel Writers was created in 1960.
Writers Guild of America Award was created in 1949.
New Zealand Writers Guild was created in 1975.
Writer's is the singular possessive form of writer, e.g. I've got writer's crampWriters' is the plural possessive form of writers, e.g. The Writers' Guild of Great Britain
Use your search engine. Type in the name of your area and "writers' guild" or "writers' club" and see what pops up!