I just finished Greg Mankiw's thought-provoking article on income inequality and redistribution. He explores both the economics and the philosophy of the issue. To understand some of the discussion, you would need to know technical economics at the level of an intermediate college course. But much of it is accessible to a general audience. I highly recommend it.
I have added a new section called recommended. It has a list of books, videos, websites, etc. that I think is worth exploring. I'll be adding to the list as time and ideas permit, so check back now and then.
Author of Economics: The Remarkable Story of How the Economy Works