Checkbox on Checkout Screen

[amplexus]

I have a complicated situation I need to implement.

I need to add an extra 10% to orders that are shipped to locations west of the mississippi.

Ideally, I'd like to implement a checkbox on one screen of the checkout process so that we can add the extra 10% by hand when we process the credit card (offline).

If there was a way to echo this checkbox value to us in the email sent to the administrators email acount, I would need to know how to implent that as well.

I realise the above is most likely a bad way to go about it, and will take considerably changing to implement correctly; and so I would greatly apreciate your input as to a better and simpler way to acheive the same results. Thank you.

[amplexus]

I figured out a different way to acheive this, so never mind. Thank you.