Have a look in the guides section , Dave shows how to fit a laguna splitter - look pretty nice.
I also know that a Seat Ibiza GTI is it? fits too, can't remember what spec and they can be bought from seat dealership for only £18 iirc. "MUFC" fitted one to his punto mk1. These are the ones that don't require that much effort into making it to fit but I'm sure you could pretty much fit any with enough time and effort gone into it.
I read a thread today on another forum about a guy fitting a honda s2000 splitter to his. It took ALOT of time - had to completely redesign the bumper but looked the nuts.
Dan