I'm trying to write something in PHP so that when a visitor clicks on my adwords ad using Internet Explorer 6, I can pull the keywords that they typed in and store them on another server. What is the best method for this? Thanks.
If you're using PHP it does not matter at all what browser is being used. Since PHP an gather the querystring from $_SERVER['QUERY_STRING'], likewise you can simply get the kw or q varibles via $_GET['q'] and $_GET['kw'].
Other than that I think you need to more clearly phrase your question especially the 'on another server' portion.