Here are a few general Shakespeare sites. Some of them require registration, which is entirely at your discretion, up to you, a decision you'll have to make -- inotherwords, you don't have to do anything you don't want to!
The Internet Movie Database
The IMDb is an invaluable resource for anyone even remotely interested in film. It is a subsididary site of amazon.com, but really it's the bible for film buffs. Here are the IMDb lisitings for all the films we see in class (including the optional viewings), as well as list of all the Shakespeare films listed on the IMDb.
Specific Play Sites
Here are some sites created for specific plays.
This page compiled by Adam B. Vary