Trainz has thousands of O Gauge train parts. Certainly one of the largest on the web and growing every week. Our specialty is Lionel train parts. We have trucks, couplers, smoke units, motors, e-units, milk cans, cattle, switch hoods, rockets, transformer parts, and all the basics too: screws, springs, rivets, & light bulbs.
We have parts for all eras of O Gauge trains also: Prewar, postwar, and modern era. In addition to Lionel, we have K-Line, MTH, Williams, and Atlas parts too!