You didn't finish the tag
<link rel="icon" type="image/png" href="http://as-photography.info/favicon.png"
This is not how you comment out in HTML.
Fix this :
The path is not to a location on the net.
<body onload="MM_preloadImages('file:///Macintosh HD/Users/andysimpson/Desktop/img/twitter-badge2','img/twitter2.gif','img/facebook2.gif','img/mail2.gif')">
And may I add the following suggestion:
Put all your CSS in an external CSS file. It makes editing my easier as everything is in one spot. As you have it, you have to open each and every page of the site to edit any changes you might wish to make in the future.