Ï'm experiencing slow resonse times with my wamp setup.
I've setup Wamp at a VPS server, 640 Megs of RAM, 320 currently in use. Normal html pages are being deliverd instantly, while my Joomla pages are taking around 8 seconds to load. Also the phpinfo page is showing up instantly.
How large are your pages? Try using Firefox with the Firebug extension and the Net option which will show you the time it takes to download each part of the page.
Do you use a number of Joomla extensions? If you have a test version of your site, you could turn on the Debug option to see how many queries each component is producing.