isnt reccomending ayn rand to someone on squat the planet like suggesting the satanic bible to a baptist congregation? She pretty much preaches letting the poor starve to death, its like the defining literature of the neo-con free market capitalism that is destroying the world(just saying)
no one mentioned edward abbey,
check out "comes a horsemen", its about the antichrist murdering people who've seen hell, or bukowski for some self deprecating depressing, yet still really good to read stuff. Read The Portable Henry Rollins, its a fast read and great book to have on your shelf, lots of really violent insight into the human psyche actually reminds me of an angry bukowski.
the painted bird by jerzy kosinski is really fucked up if thats what your looking for, its about a little boy hiding out during the holocaust and a series of fucked up events follow
But def consider a peoples history of the untied states by howard zinn, probably the most violent book of all, and its all true, insightful, and gives you perspective on where we are today.