Other
Hoover Institution: Documents From the Terror
Documents from the Hoover Institution detailing the gruesome details of the "reign of terror" that Stalin instituted against the Soviet people from 1936 to 1938 with some earlier and later accounts.
ibiblio
Ibiblio: Collectivization and Industrialization
Excellent site that is part of a larger collection of documents from the Soviet System. Site gives a good explanation of the Five-Year plans put into effect by Stalin.