If there is one font that is used more than any for Goth slogans, t-shirts and banners it's Fc Caslon Antique. As a font it has a long heritage, it was used on the American Declaration of Independance no less.

It was the type face for the EdG&R logo and was used on many of the defining Goth t-shirts have have become widespread in the subculture such as the "Goth Tart", "Goth Slut" and the EdG&R t-shirt.

It is one of the charms of the Goth subculture that unlike many other music or fasion based subcultures in the UK it alown, IMHO is the only one that has a cultural bias as to its typeface.