Good Reading - A Guide For Serious Readers Arthur Waldhorn, et. al. 23rd Edition of a book first published in 1932 that now lists over 3,000 titles in an attempt to present a complete list of the best books in 33 different areas, including various sciences, historical periods, literary types, etc.

This is very nearly the only book that you'll ever need to consult in order to get ideas for good books to read.  The book is organized into many different areas and presents lists of the "best" book in each subject or format, compiled by various experts.

For non-fiction topics, picking any of the subject areas and browsing the list of books presented, you're liable to see a pretty comprehensive overview of all work published in that particular field.  For fiction, you get a pretty complete list of some of the greatest books in the chosen genre.

As an example of some of the lists of fiction, Chapter 12, "The Novel", contains the following sub-sections:

19th-Century Continental Novels
20th-Century Continental Novels
19th-Century British Novels
20th-Century British Novels
19th-Century American Novels
20th-Century American Novels
        1900-1945
        1945-Present

Other chapters for Literary Types include: The Short Story, Poetry, Drama, Biography, Essays/Letters/Criticism, Science Fiction, Mystery Fiction and Language and Communications.

As an example of some of the chapters contains lists of books for the Humanities and Social Sciences, the chapters include: Visual Arts and Performing Arts, Philosophy, Psychology, Religion, History, Politics, Economics, Anthropology, Sociology and Women's Studies.

Bottom line--a great source for the "what should I read next" blues.