The new silentsparrow (the old location is now the Ozimals Orientation area!) is an excellent source for high quality gothic suits for men and women. They also have a nice selection of gowns, corsets, waistcoats, and an eclectic mix of items.
I've reviewed other suits from silentsparrow before, including the Ryou Suit and the Corbie Suit. Here I am modelling the Batty Suit with tails and jacket.