Curious about different editions of Hamlet, appropriation in different parts of the world, or just about anything else Hamlet-related? This is the HamletWorks web site created by Bernice Kliman and colleagues. http://www.leoyan.com/global-language.com/ENFOLDED/
See also quartos.org, where you can look up and even annotate and share several different quarto texts of Hamlet.
More links and resources at Hamlet Online. Full text with glossary links online at MIT: http://shakespeare.mit.edu/hamlet/.