Movies has been used for this purpose for a long time, and Cheryl has done an excellent job covering older transgender oriented movies over at her site Lost in Transgender.
She writes about the backstory, the actors, the directors and the times the movies were made.
The movies can sometimes be hard to get hold of, but by doing some internet searches you will be able to find some of them.
She also uses the site to promote the Tranisa crossdressing and gender bender videos in between the historical articles.
Visit Lost in Transgender here!