Do It Yourself! Obviously, this blog can only present a tiny fraction of the cars that are available out there. But you can easily find out stuff for yourself, without even buying a ticket to Sao Paulo, Santiago or St. Petersburg (unless, of course, you want a test drive). Instead of traveling the world, you can travel the web. This page lists or links to a few tools that will help you do that.
Fuel Efficiency conversion
US (mpg) == 235 / EUR (liters/100km)
US (mpg) = 2.35 * ASIA (km/liter)
US (mpgUS) = 0.83 * IMP (mpgimp)
Unit converter - mpg, L/100km, g CO2/km, etc.
Fuel Efficiency translation
How to estimate real-life mileage from stated fuel economies.
How to avoid fainting when reading cars' List Price outside the US.
Most car makers' websites are aimed at the local consumer. If you want an overview a good place to start is the Wikipedia pages. For each model you can find out the history, the names it goes by in different parts of the world, what other make&model cars share the same engine, and other neat tidbits.
Strategies for navigating non-English websites. Hint: lean on an online dictionary such as translate.google.com