You have your settings correct
Charge Tax All: Not Checked
Tax Rate: blank
Use Tax Tables: Checked
Default Country: United States
Home State: Minnesota
You can set the tax rate to 7.5% for all customers who buy from Minn. by adding the highlighted section below to the following stored proc or just running this stored proc from sql mgmt studio. We will be adding this to the cart settings screen in the next release.
ALTER PROCEDURE [dbo].[Smith_GetTaxRate]
@CityName VARCHAR(255) ,
@State VARCHAR(50)
AS
IF ( @State = 'CT')
BEGIN
SELECT '6' AS [TaxRate]
END
ELSE IF ( @State = 'MI')
BEGIN
SELECT '6.5' AS [TaxRate]
END
ELSE IF ( @State = 'MN')
BEGIN
SELECT '7.5' AS [TaxRate]
END
ELSE
BEGIN
SELECT [TaxRate] FROM Smith_Tax
WHERE lower([City]) like lower(@CityName)
AND lower([State]) like (@State)
END