There are several websites dedicated to the reading order of the collected editions of the Superman trade paperbacks, but all of them are either incomplete or outdated.
You have:
Superman Golden Age Omnibus series 1-7,
World's Finest Silver Age Omnibus 1-2
Supergirl The Silver Age Omnibus 1-2
The Superman Chronicles 1-10
Superman Archive Editions 1-8,
Action Comics Archive Editions 1-5,
Superman World's Finest Archive Editions 1-2,
Showcase Presents World's Finest Comics 1-4,
Showcase Presents Superman Family 1-4,
Showcase Presents Supergirl 1-2,
Showcase Presents Superman 1-4
Showcase Presents DC Comics Presents 1-2
Superman in the Forties
Superman in the Fifties
Superman in the Sixties
Superman in the Seventies
Superman in the Eighties
Kryptonite Nevermore
What else is there?