You can search the Orbis catalog for sources of film reviews by using the example subject headings below as a guide.
These subject searches also provide a way to find books which collect reviews, such as Pauline Kael's 5001 Nights at the Movies, and American Movie Critics: An Anthology From the Silents Until Now (ed. Phillip Lopate).
The following list covers additional sources of film reviews, primarily "authoritative" ones but also a handful of "popular" review websites and blogs. Some of these resources list reviews published before the mid 1970s -- they might be the only way to find reviews published when an older film was released.