FooSales will look at your store’s address for guest customers. You can set your address under ‘WooCommerce -> Settings -> General‘.
If you’ve set a tax rate for your State under ‘WooCommerce -> Settings -> Tax -> Standard Rates‘ then FooSales will use this tax rate. If there is no tax rate set for your State then no tax will be added.
We strongly recommend that you read through the documentation on Setting up Taxes in WooCommerce carefully and consult with a qualified tax practitioner if necessary before using FooSales.