Catching Fire is the story of Katniss Everdeen, citizen of the reservation-cum-labor camp known as District 12, part of a larger dystopian society called Panem ruled over by the wealthy and autocratic Capital. Katniss is forced by the Capital to participate, for the second time, in a brutal death match called the Hunger Games against other citizens of Panem. Katniss's private life is placed under an intrusive microscope as her manufactured romance with fellow survivor Peeta becomes increasingly popular. The story is a cautionary tale about violence and obsessive voyeurism.
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 original provider of professionally-written study guides, Cliffs Notes were available in print form before the Internet even existed. Their content is very comprehensive and includes an analysis of characters, detailed chapter by chapter summaries, critical essays, essay topics, and many other sections.
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.