Traffic Law:

Air Bags - National Highway Traffic Safety Administration (NHTSA) - Important information on vehicles with air bags.
Aggressive Driving Enforcement
Automated Traffic Law Enforcement Model Law - NHTSA
Department of Motor Vehicles Guide
Equipment and Safety, Crash Tests and Rollover Ratings, Defects and Recalls
FindLaw: Transportation Law
Insurance Institute for Highway Safety
LII: State Statutes - Streets and Highways
National Committee on Uniform Traffic Laws & Ordinances
National Highway Traffic Safety Administration - NHTSA
National Traffic Law Center - APRI
Recall Information - NHTSA - Recall Searches by make, model, year. Child Safety Seat Recalls. Monthly Recall Reports. School Bus Recalls.
State Traffic and Speed Laws
State Transportation Sites - by U.S. Department of Transportation, Federal Highway Administration
Traffic Injury Research Foundation
Traffic Law: Free Legal Information
Traffic Ticket Law - ExpertLaw
Traffic Ticket and Violations - FindLaw
U.S. Department of Transportation
United States Speed Laws