Confluence is the Willamette Valley's Mixed Gala Chorus. A number of its members are transgendered. Their September newsletter focused on these transgender members. Articles in the issue include;
What is Transgender?
My Trip to Thailand
Some of Our Trans Singers Speak Out
Confluence Web Site: http://www.confluencechorus.org
Newsletter: http://www.confluencechorus.org/Newsletters/Newsltr%20Sept%202006.pdf
Confluence is a great group. Perhaps you'll want to catch a performance or possibly even join the group.