If you’re really into it, you can read the 1667, 10 book version of Paradise Lost in PDF format here. This won’t help you for the GRE of course, but it might remind you why you’re taking this test in the first place.
It’s generally agreed that “Paradise Lost” is the most frequently occurring text on the GRE. Read it, it’s awesome. I found it hard to absorb in audio form, but still it’s worth a shot. You can actually download it as a podcast from the University of Cambridge, or as a zip file from booksshouldbefree.com. I’d recommend Cambridge, but you can also listen to the good folks at Librivox, below.
“Paradise Lost” is an epic poem in blank verse, and was first published in 1667 in ten books. A second edition came out in 1674, redivided into twelve books The poem relates the story of the Fall of Man through the temptation of Adam and Eve. Milton’s purpose, as stated in Book I, is to “justify the ways of God to men”