Here is a website (italiano) that you can plug in a surname (last name) and see what location(s) in Italy it would be predominantly found:

http://gens.labo.net/en/cognomi/

Also a link to search your surname in the USA (see the text box on the left of the page marked "Cerca anche in:http://gens.labo.net/img/flag_us.gif (http://www.gens-us.net/map/genera.html?cognome=) USA (http://www.gens-us.net/map/genera.html?cognome=)".

that's a great link !! This will surely help with my family history reasearch:D

that website is great! really cool to check out, thanks for sharing