Does anyone know of a good Auto Loan Calculator?

Im my opinion, the best Auto Loan Calculator is this one:

http://www.xgadget.net/auto-loan-calculator.html

This is the one you already stated. Here are some important tips with regards to Auto Loan Calculators.

Buying a car, all at once, to me seems like an irrational thing.
Because of this, everyone, when considering buying a car, should really do their homework to see if they can afford a car loan and to see what type of auto loan offers they can receive. Thats why using a free auto loan calculator is the most rational thing.