At the start of the game, Rusty will be the only one who challenges you to a race. To accept, simply click on his vehicle. You can also go in search of people to race by visiting some of the game's Hot Spots (accessible via the GPS). You will find cars in the parking lots for a few of the game's Hot Spots. You can also, of course, race against your friends.
If you mouse-over a car, you can see its power lined up against the amount of money on offer should you be able to beat it in a race.
To physically win a race, you obviously must be the first car across the line. You need to click once, when the countdown timer reaches zero. Then, you will see a rev meter. Each time the line moves across the green strip on the meter, you must click again. This simulates changing gear. Change gear too late and you will slow down and lose points. Change gear too early, and suffer a similar fate. If you can consistently change gear accurately, and are in a good enough car, you will win plenty of races. You get bonus points for changing gear exactly on the green marker, doubling your reward, but this runs the greater risk of changing late and losing points. This allows you to take on more powerful cars. The winner is based on the 'score', which is determined by the quality of your gear changes.
It is a good tactic to buy one car and spend a lot of money on performance upgrades. These can drastically improve weak cars and be far cheaper than investing in expensive high-end cars, yet allow you to beat some of the game's best.
Daytona International Speedway:
The Daytona International Speedway section of Car Town is quite a robust area that is accurately modeled on the real racing environment of the Daytona circuit. The first thing to do in undertaking a Speedway career is to build your stock car. With that done, you have another racing element. Click and hold this time for the length of the green lines running along the bottom of the screen.
If you win a race, you get to keep the stock car that you picked! It takes 6 hours to prepare for a race, so bear this in mind when deciding to take part in one.
Indianapolis Motor Speedway:
Very similar to the Daytona Speedway, the Indianapolis Motor Speedway requires you to pick your driver from all the available teams, then build your car. The racing mechanics are exactly the same as for Daytona, except you first have to qualify for the season. Once you win that race, you are entitled to take part in a full season of 17 tracks. Should you be the overall winner, you will unlock a trailer for your driver.
NASCAR Pro Championship:
Initially, in the NASCAR Pro Championship series, you have to race in qualifying sessions, hoping to perform well and attract sponsorship. With that, you will be given a place in the Pro-Championship. The Pro-Championship consists of 3 races. Win them all to gain fans, experience and achievements.
High Stakes Track:
There used to be the opportunity for you to race against other players of Car Town and place bets on who would win. This could be against anyone playing the game, rather than just your friends. It is currently shut down, however.