I would recommend you to check your receipt of the payment including personal checks and credit card statements. If you purchased from a dealership, you might be able to contact them to obtain the information from their record. You might not have paid any sales tax if you live in one of the five states below.
Here is some additional information for your reference:
Whether you're buying a new car or a used car, or even leasing a car, you'll have to pay state sales tax. Nearly every state has a sales tax, ranging from under 3 percent to over 8 percent.
There are currently five states that do not have a sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. Municipalities within these states can still levy taxes. Check locally to see if any sales taxes apply to your new car purchase.
