Being near clueless in the area of auto-detailing, I thought I'd post a link to the single most useful document I've found to educate me on how to take care of my spyder (I only get to drool over the thought of owning an Elise for now)
It was written up by Dev on spyderchat, and is perfectly named 'Exterior Detailing 101'.
http://www.spyderchat.com/phpBB/viewtopic.php?t=20887