Overview
There are a few different reports you can use to view sales tax information but, in our opinion, the best one is the "End of day reconciliation" report. This report is a one stop shop for a lot of great data including sales tax information.
Procedure
Go to Tools > End of day reconciliation > filter for dates and the location you're interested in. At the bottom of this report, you'll see:
Tax Collected - this is how much of each type of tax you collected
Taxable Sales - this is how many dollars of sales that were run under each tax type. This is typically the information states ask for when you go to pay sales tax.
Both of these are just snapshots of the real / comprehensive report and you can drill down into the report by clicking on the title:
You could drill down into the "Taxable Sales" report and group it by tax type and department for example - if you wanted to find products being sold with the wrong tax type (IE - all Wine sales should have 10% sales tax assigned to it).