Speedtax integration

Hello developers,

I am looking to integrate speedtax (www.speedtax.com) with my shopping cart. I have attached the files associated with this integration. Speedtax is a system that will be called on the checkout page that returns tax rates for the jurisdiction entered in by the visitor. Once the call happens, the tax associated with the ship to address will be applied to the checkout page.

As anyone developed or seen anything similar to this?

Thanks in advance,