I recently read Fast, Cheap and Written That Way: Top Screenwriters on Writing for Low-Budget Movies by John Gaspard. So many classic movies are discussed. Made by people like John Cassavettes, William Greaves, John Carpenter, Ron Howard, Roger Corman, Jon Favreau, Henry Jaglom, Steven Soderbergh, etc,. Gaspard talks about not just where they got the money, but how the movies were made and what the conditions were. You get to see a lot of mistakes as well as techniques that worked. He covers the whole modern era of breakthrough films, but you have to imagine for all these success stories there are thousands of movies out there that died the death of forgotten obscurity.
But one of favorite things about the book is the inside covers. Tons of books are listed which are crucial to making movies and writing screenplays.