How Common Is the Last Name Prado In Sicily?

Not particularly common. In all of Italy, there are 88 listings in the Pagine Bianchi a href="http://www.paginebianche.it/index.html" rel="nofollow"http://www.paginebianche.it/index.html/a for the name Prado. Some of those are in Sicily - a quick search shows a couple in Noto, for example, but some are also in the north of Italy.