These are some very good links to information about Gothic Literature and sources to e-texts of many stories. I have not check for sure, but I belive you can get to e-texts of the stories that Jet has mentioned. They cover the early period of Gothic Literature starting in the late 1700s through turn of the century. Gothic covers a large period of time and it is interesting to see how the literature progressed over 100 plus years.
And of course Project Guttenburg is a wonderful source for free online books.