World Cars 1981, by the Automobile Club of Italy. Pelham, N.Y.: Herald Books. $37.50.

This is probably the most complete compilation of car names, data, and prices to be found anywhere. Compiled each year by the Automobile Club of Italy and published in the US by Herald Books, "World Cars" takes the reader from Detroit to Tokyo, with stopovers at every other auto-building spot in the world in both directions and makes a lot of fun of the journey, to boot.

The 440-page tome gives the facts on cars that the majority of the world's motorists have never heard of, much less seen. How many of the world's car drivers have ever sat in a Trabant (East Germany), a Monteverdi (Switzerland), or a DMG (Philippines)?

The Aurora, Dacunha, Mebea, and Dankar; the De Courville, Era, Mallalieu, and Kougar, and hundreds more, are all here between the covers of "World Cars 1981."

Included in the journey are 1,100 photos, some of them in bright color, of the cars from A to Z. The global "tour" makes stops in 35 different countries on every continent but the frozen south, Antarctica. It's cheaper than renting a car, of course, yet the price still seems high -- $37.50. Inflation, the publisher replies.

This almost four-pound catalog spotlights a 26-page section on some of the world's top coachbuilders -- Pininfarina, Giugiaro of Ital Design, and Ghia, among them.

An outline of the history, structure, and activities of the world's cars manufacturers and coachbuilders is included as well.