For those who can comprehend the Teutonic, here's a wealth of info by a German living in North-Eastern Italy:
http://www.fliegen-in-italien.de For one thing, it explains why many places have avgas available but only to locals/club members: Italian regulations seem to allow a tax advantage to such sales. Reading between the lines - which was never my strong point - I seem to imagine it is "often" possible to arrange something, but I can well understand nobody is going to state this publicly. Especially on a place as notorious as this.