Opet mislim da ćeš ovako najprije ubosti sa RegEx...
PHP kôd:
$html = '<head>
<meta name="description" content="Free Web tutorials" />
<meta name="keywords" content="HTML,CSS,XML,JavaScript" />
<meta name="author" content="Hege Refsnes" />
<meta http-equiv="refresh" content="0; url=http://example.com/">
</head>';
preg_match('#url.*?=.*?([^"\>\s]+)#is', $html, $matches);
echo $matches[1];
@Dinke, fali ti case insensitive i single/multi line modifier, neki siteovi stavljaju META velikim itd...