Howdy Joe,
With the exception of Pietta, which I have just found, there don't seem to be any handy available lists of serial numbers versus year of manufacture for Italian guns. The Italians put a mark on the barrel or frame which can be referenced to a year of manufacture, and that is what Bangor Dan was talking about. This list of marks can be found on Bluebook's website, and I think elsewhere as well. When I just went to Bluebook's page that I had bookmarked, I found it to be "404 - Not Found". Checked further and found that Bluebook has changed their website, and the new page for the Italian year codes is now:
http://bluebookofgunvalues.com/Info/PDF/Powder/PiettaandItalianSerial.pdfInteresting thing is that this page now does list serial numbers of Pietta handguns corresponding to year of manufacture. But only Pietta. For other Italian guns, at the bottom of that page they still list the codes.
Also, in some cases you can contact the importer and find this info. For instance, if a gun is a Cimarron, a call to them with the serial number can get you the year they received it (or sold it?). If the gun is a generic Uberti USA, then possibly an email to Uberti will get you the info. But if you can find the date-code marking on the gun, the above referenced web page can give you the info.