Here are some interesting and entertaining links that I've found on the internet. I promise...no rickrolls in this one.
(Some of these contains some spoilers, so you might not get some of the jokes until you finish the novel.)
Here is a webcomic, in which the cast of Watchmen have been replaced with newspaper comic characters:
Here's an animated trailer for Saturday Morning Watchmen, a parody, almost akin to the intro of Teenage Mutant Ninja Turtles from when we were kids. I love some of the irony. "Rorschach's friends to the animals!"