Internet Movie Database Though started as a database for movies it now includes info on TV shows.
Many episode lists some of which have more detailed guides.
Sitcoms Online Concentrates on guides for sitcoms. Scifi Site WWW pages Has guides for some science fiction and fantasy shows. Rutgers University sci-fi episode guide archive Another site with science fiction and fantasy guides. Sites of Individuals These are sites of people that have done a number of episode guides. Some of the guides are on the general sites listed above though not all of them are and some might be more up to date.