Here's a link to the PA page
of the Freedom to Marry Coalition. They may be of some help.
Also, there used to be a large lgbt activist community in Pittsburgh. However i've been out of that loop for many years. The only name i can remember is Billy Hileman, who might be a helpful resource if he's still in the Pgh area. He was the founder of Pgh's ACTUP cell. Maybe someone there can look him up? I think he may still work for Pittsburgh Public Schools.