Stanford University
Ancient Skepticism/stanford Encyclopedia of Philosophy
An excellent, detailed, and lengthy overview of the ancient Skeptic tradition. Divides into Pyrrhonic and Academic Skepticism. Includes many quotes and a full bibliography as well. A superb treatment of the subject.
Internet Encyclopedia of Philosophy
Internet Encyclopedia of Philosophy: Ancient Greek Skepticism
This site from the Internet Encyclopedia of Philosophy is an excellent, brief introduction to the major thinkers in the ancient Skeptic tradition. Divides the movement into early Pyrrhonism, Academic skepticism, and post-Academic...