Thanks. This is the problem. I am using PayPal, so they just give me the html for the button to add to my page. They do not do shipping by state which is what I need to do. So I figured I'll get the state from the user and figure out the shipping and replace their variable. However I'm not sure how to intercept their code. Once the user hits the button it takes them to the shopping cart. I want a pop up after the user hits the button, before the shopping cart so that I can change the shopping cart. Here is Paypal's code:
<form action="
method="post">
<input type="hidden" name="cmd" value="click">
<input type="hidden" name="business" value="anon@anon.com">
<input type="hidden" name="item_name" value="NameOfItem">
<input type="hidden" name="amount" value="36.00">
<input type="hidden" name="shipping" value="10.00">
<input type="hidden" name="return" value="
<input type="hidden" name="cancel_return" value="
<input type="hidden" name="currency_code" value="USD">
<input type="hidden" name="lc" value="US">
<input type="image" src="image.gif" border="0" name="submit" alt="Make payments with PayPal - it's fast, free and secure!">
</form>