I just ordered a manual on CD off ebay. Looks to be the item UKCHIRS was referring to. I'll update you guys on what its like upon receipt. It doesn't look like its too detailed, the pic only shows 286 pages or so (i'm sure Boxsters have more problems than this that need fixing....). Here's the link
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=8011214830
I also have my motor bookshop chasing up what it can get in print form.