I've seen the film Fight Club many times, have the DVD and Blu-ray.
Yet I've yet to read the novel.
I gotta vote Damned. Lullaby was an old favorite too. But Damned... god I loved that one.
Fight Club, Invisible Monsters, Diary.
I really enjoyed all his novels though have yet to read Damn and Doomed.
Survivor has always been my favorite. And of course I loved Fight Club and Lullaby.
But Rant is a standout for me after several novels that didn't live up to the standards of his earlier work.
At Green Building,
Honestly I'd suggests starting with Fight Club and reading in order of when they were released.
Fight CLub is a quick read and all his early work was fantastic.
Get Haunted, read "Guts." I think that's his masterpiece.