Quick Ajax update to a .js form

Currently have a form which takes a set amount of details and then calculates a price - then sends this information to paypal to be processed. I need to add a radio button to pay by cash also at the bottom and the same details to be send to an email address instead of sent to paypal.

So simply to add a radio button and send the already gathered details to an email. Its a very quick job - 20 mins max.

Needs to be done urgently.