Charles Reznikoff, Gilbert Sorrentino, Paul Blackburn, August Kleinzahler, Edward Dorn, Jonathan Williams, Robert Creeley, and Basil Bunting are some 20th century poets I've enjoyed reading.
I remember reading somewhere (believe it was in John Berendt's book on Venice) that Ezra Pound's wife/companion wouldn't allow people to visit him late in his life unless they were able to quote some lines from his poetry. As I sit here, I realize that I can quote very few lines from the above poets, so I wonder how well I've read their poems - not well at all, I fear.