Die Hard: Official site by Twentieth Century Fox, with information on the trilogy and the game, plus several video clips.
Die Hard Dedication Page: Gallery of images from the movies.
Fred's Die Hard Trilogy: A fan site with movie scripts, "Die Hard 4" rumours, pictures, quotes, and links.
KillerMovies - Die Hard 4: News about the upcoming sequel.
Nakatomi Plaza: Fan site with quotes, images, and information about the trilogy.
UML's Die Hard 4 Page: Speculation and news about an upcoming fourth part of the Die Hard series.