Italy is perhaps that country in the world which have the
largest selection og different grapes, native or not. One
believes the number is around 2000. Of these around 1000 is
known and 400 recommended and allowed used in Italys regulated
appelations. This page gives an index of the more rare and
unknown grapes one finds in this diversity. That means you
will not find references to Sangiovese, Nebbiolo or Trebbiano,
but you can search for those strange grapes that you sometimes
bump into and read a litte more about their placing in the italian
wine-scene. Good reading.