Mostly ground forces oriented, but still useful and educational (in PDF):
Soviet Army Operational and Tactics
Soviet Army Specialized Warfare and Rear Area Support
Soviet Army Troops, Organization and Equipment
Soviet Motorized Rifle Battalion
Soviet Motorized Rifle Company
Soviet Tank Battalion Tactics
Soviet Tank Company Tactics
Heavy OPFOR Tactical Handbook
Heavy OPFOR Operational Art Handbook
NATO order of battle 1989
Bundeswehr order of battle
West German Territorial Army order of battle
Bundeswehr HQ units order of battle
Group of Soviet Forces in Germany, 1988 (zip)
Central Group of Forces, 1988
Northern Group of Forces, 1988
US intelligence and Soviet armor