thesociologist:

We do not disagree with Jonathan Franzen on the beauty and meanings behind the permanence of books; stories that are written ought to be preserved in more tangible forms. But when it comes to knowledge, we do not see any harm in sharing. Aside from the time and effort put in by the writers, the rest is just glue and paper on the publishing side (not that we are undermining the efforts of hardworking editors and typesetters).

We are not advocating piracy, but any worthy scholars should be pleased to share their theories and findings. Ideas and thoughts possess immortality, more so than papers. And please, think about the trees! So here goes, equality and accessibility for anyone in pursuit of knowledge. Or rather, PDFs of some works in sociology or the social sciences in general.

• The Blackwell Guide to the Philosophy of the Social Sciences (2003)
• The Blackwell Companion to Major Classical Social Theorists (2003)
• The Blackwell Companion to Sociology of Religion (2003)
• Pierre Bourdieu (1984), Distinction: A Social Critique of the Judgement of Taste
• Albert Camus (1942), The Stranger
• Jacques Derrida (1997), The Politics of Friendship 
• Émile Durkheim (1897), Suicide
• Émile Durkheim (1938), The Rules of Sociological Method
• Michel Foucault (1990), Politics, Philosophy, Culture: Interviews and Other Writings, 1977-1984
• Michel Foucault (2000), Power: Essential Works of Foucault, 1954-1984
• Erich Fromm (1955), The Sane Society
• David Harvey (2007), The Limits to Capital
• Aldous Huxley (1932), Brave New World
• Niccolò Machiavelli (1532), The Prince
• Marxism after Marx: An Introduction (1979)
• Max Weber (1930), The Protestant Ethic and the Spirit of Capitalism
• Slavoj Žižek (2001), On Belief
• Žižek and Politics, A Critical Introduction (2010)

If you have a stricter legal compass, Project Gutenberg offers a few works specific to the discipline, along with the likes of Dickens and Joyce in its collection, which can be found in readings of countless sociology classes:

• Theory of the Leisure Class by Thorstein Veblen
• Sociology and Modern Social Problems by Charles A. Ellwood
• The Communist Manifesto by Friedrich Engels and Karl Marx
• Leviathan by Thomas Hobbes
• Walden by Henry David Thoreau
• Beyond Good and Evil by Friedrich Wilhelm Nietzsche
• Bleak House by Charles Dickens
• Dubliners by James Joyce

For lighter foundational reading materials, consult your friendly neighbourhood Wikibook, “Introduction to Sociology”.

Oh my, you lot, look at this!

(and I actually need that Fromm reading for one of my classes this semester!)

(Plus, Richard Siken is a gorgeous poet, though that is slightly off topic)