Rebecca is the story of a nameless young woman who marries the wealthy and urbane Mr. de Winter in the wake of the death of his first wife, the titular Rebecca. The new Mrs. de Winter is tormented at her husband's mansion, Manderley, by the cruel and manipulative housekeeper Mrs. Danvers. The novel deals with emotional abuse, the nature of relationships, the fears faced by young wives, and with the obsessive cult of personality the late Rebecca constructed for herself.
Boasting the largest collection of book summaries, BookRags is the best option for titles you can't find elsewhere. They offer all of the basics (quotes, chapter summary, characters, historical context, literary criticism) but also walk through a few major topics that recur throughout the book, which can be particularly useful for essay writing.
The most popular website for book notes. SparkNotes was created by students for students, and their summaries are accessible and extremely well-written. Besides the usual plot overview, chapter summaries, and character analysis, SparkNotes differentiates itself with a section discussing themes, motifs, and symbols.
You won't get any frills with GradeSaver -- just the content you expect. Their study guides include a full plot summary, themes and character analysis, study questions, and the e-text of the book. One hidden gem is their collection of literature essays, but you'll have to pay for it.
If you're bored by traditional book notes, try Shmoop! They write their summaries in an approachable, entertaining style. Their comprehensive offering includes chapter by chapter summaries, themes, quotes, character analysis, study quizzes, and even flash cards and infographics.