Add newsletter xml to signup forms.

I need someone to implement a very simple newsletter api that my new users to my newletter database when they signup on my [login to view URL] xml script is simple as it will catch the first name, last name, and email and store it to the list. There are a total 3 signup pages that work exactly the same. So when you do 1 page, the other 2 can be done very quickly. Here's how it works When a customer enters there details in the signup form, their info is automatically added to one list via the xml, and on the signup form, there is also a newsletter option, if the user select it, they will be also added to the other list. I have include the add to newsletter api and and one of the signup forms. Currently the signup form were implement so that the users go directly to newletter database, but i soon discover the api is easier and more accurate. also here is how api works https://www.interspire.com/support/kb/questions/1217/Email+Marketer+XML+API+usage+and+examples