Stanford Encyclopedia of Philosophy: Free Will

An overview of theories of free will and the problems that they raise. By Timothy O'Connor.
http://plato.stanford.edu/entries/freewill/

Free Will, Determinism, and Moral Responsibility - The Whole Thing in Brief

Ted Honderich's (still quite long) summary of a deterministic philosophy of mind, and its consequences for our fundamental attitudes.
http://www.ucl.ac.uk/~uctytho/ted12.htm

Who's Afraid of Determinism? Rethinking Causes and Possibilities

A chapter from the 'The Free Will Handbook' (edited by Robert Kane, 2002) by Christopher Taylor and Daniel Dennett.
http://ase.tufts.edu/cogstud/papers/kitdraft.htm

Lecture Notes on Free Will and Determinism - Prof. Norman Swartz

Discusses the various problems raised by different concepts of determinism, and presents an argument that physical determinism is compatible with free will.
http://www.sfu.ca/philosophy/swartz/freewill1.htm

Determinism as True, Compatibilism and Incompatibilism as Both False, and the Real Problem

A critique of the view that quantum theory disproves determinism, and an argument that freedom is simultaneously compatible and incompatible with determinism. By Prof. Ted Honderich.
http://www.ucl.ac.uk/~uctytho/detkanebook.html

The Determinism and Freedom Philosophy Website

A comprehensive collection of important papers on the philosophy of free will, freedom and determinism. By Prof. Ted Honderich.
http://www.ucl.ac.uk/~uctytho/dfwIntroIndex.htm

Online Papers on Consciousness: Free Will

Section on free will from David Chalmers' site.
http://www.u.arizona.edu/~chalmers/online2.html#freewill

Stanford Encyclopedia of Philosophy: Incompatibilist (Nondeterministic) Theories of Free Will

Randolph Clarke's survey of theories of freedom according to which it is inconsistent with causal determinism.
http://plato.stanford.edu/entries/incompatibilism-theories/

Naturalism.Org - Free Will

A series of essays offering a naturalistic critique of libertarian free will, arguing that such freedom is illusory, and also unnecessary to ground our moral practices.
http://www.naturalism.org/freewill.htm

An In-Depth Analysis of Volitional Science

Volitional science is the attempted integration of cognitive science with the structure of society. It argues convincingly for the existence of free will. Is a cross-disciplinary study of cog sci, game theory, social science and Austrian economics.
http://chasholloway.com/volitionalscience/