Knowledgebase
How to add fixed product taxes in Magento
To add a fixed amount of money as a tax to a product(s) you need to do a few things.
To enable fixed product taxes, log in to the admin panel of your Magento and go to System>Configuration>Tax button in the Sales section on the left>Fixed Product Taxes panel on the right. Set the Enable FPT option to Yes and click on the Save Config button.
Attributes are used to add fixed product taxes. So you need to create a new attribute from Catalog>Attributes>Manage Attributes. When you create the attribute you have to set the option Catalog Input Type for Store Owner to Fixed Product Tax. Then you can add that attribute to any of your attribute sets. You can add fixed product taxes to each product that is created with an attribute set that contains an attribute for fixed tax.
For some more details and screenshots you can also check out the tutorial on managing fixed product taxes in Magento.