Mason:
I echo what Patrick said. I would only add that since you have limited funds and just starting out put the passenger cars aside for a while and start with freight cars. The best places to get inexpensive cars are your local swap meets. With freight cars your RR has a whole lot of reasons to exist. As opposed to passenger cars whose sole function is to pick up and drop off passengers, having freight allows you to set up all the spurs (sidings) you can afford and place structures for both providers of raw material (coal mine, oil depot, asphalt dealers, cement plants, grain elevators etc) and consumers (power plants, concrete dealers, oil dealers, mills etc).
So besides watching your trains go around and around (nothing wrong with this - I have been know to sit with a cup of coffee and just watch my trains go around) you can also pick up loaded cars from a provider and drop off the cars to each consumer, pick up empties and bring them back to the providers. You can also set up track and play switching games (google John Allen's Timesaver game).
Have fun
Joe
