One of the things that lately has brought more tourism to Sitges is its gay fame. Homosexuals, mostly men, from all over the world come to Sitges to meet new "friends". The open minded locals tolerate this relatively new kind of tourism well. I am sorry, but I do not have information about gay sites. I can only assure you there are plenty of them.
By the way, do you know why gays always choose the best places to settle? Just think about the most beautiful cities in the world. Almost all of them have an active gay life: San Francisco, Sydney, Sitges ....