Handle Dynamic Input Fields In Post Method Using PHP

I have a dynamic form, when a button is clicked 3 more fields appear, the function is to colect for example from date [02/02/2010] to date [10/02/2010] equals price [250$] per week and if you want another period just click the button and 3 more fields appear. How do I get all this data to PHP?

<script type="text/javascript">
var counter = 3;
function addNew() {
// Get the main Div in which all the other divs will be added
var mainContainer = document.getElementById('mainContainer');
// Create a new div for holding text and button input elements
var newDiv = document.createElement('div');
[Code]...