you could start by browsing here
http://www.ibiza-spotlight.com/villas/
or if you'd like to be more specific in your requirements modern, rustic, proximity to a dirt track, ideal for a second honeymoon, with neighbours who love house music at 200 db, that kind of thing, i'm sure someone will be able to help without the necessity of a link to another site which sells accommodation like wot spotlike does.