Appearance money is a payment a promoter negotiates in advance with a specific driver or team to bring the car to a given event, paid for showing up and racing regardless of where the car finishes.
Appearance money is a private arrangement, which is why it never appears on a payout sheet. A promoter who wants a name in the pits — a touring star at a weekly show — negotiates a number before the hauler leaves, and the car collects whether it wins the feature or scatters the motor in hot laps. That is the line between this and tow money: tow money is a small published amount the track pays any car that shows and runs, while appearance money is negotiated with one competitor in advance. Vocabulary is not standardized — “show money” gets used for both, and some racers call it a deal. Get the terms in writing, and treat it like purse income at tax time. General education, not tax advice.
A handshake deal you never wrote down is the easiest money in racing to lose, and the easiest income to forget you owe tax on.