Just had a scroll through my very unofficial and very basic Register Thread, no luck there. You could try this Link to the World Wide Register, there is a Link there that gets you to the Spread Sheet.
As Kev has said Alex Jupe runs the official UK Register though I don't know how many people have registered. I'm one of the guilty ones and haven't registered on either.
Be nice if you Post this in our little Register Thread here too, as it's a " Sticky " it's always on top of the pile of the Posts and so will be prominent for longer.
Good luck and keep us informed.
Alfa Romeo Alfetta GTV6 1980-1987 Worldwide Registry Thread - Alfa Romeo Bulletin Board & Forums