Release and Re-Release Dates History?

Does anyone know of a source that includes re-release dates of films, as well as the original release date?

I spent much of my childhood with friends at the movies on Saturday afternoons, and remember seeing this at the theater on one of those Saturdays. But I would have been 8 years old! This is true of dozens of these great old sci-fi/horror films...I can remember seeing them at the theater, usually as part of the Saturday matinee: two films and five cartoons every week! It's not impossible that I used to walk quite a way to the theater with my friends and no adults, after all it was a simpler time back then, yadda yadda yadda, but I'm wondering if some of those films were re-releases. (Although I remember seeing previews for the coming weeks' offerings, and they were, indeed, new releases according to Famous Monsters magazine, my favorite magazine at the time.)