3.1 - San Pablo’s Curia Metropolitana
3.2 - If you do not know which Comune your Italian ancestor was from, other useful place to look for is the Immigrant Board, where immigrant stayed for one or two days until they where registered. The found here is very accurate.
http://www.apellidositalianos.com.ar/base/listadoAp.asp
This Argentinean website provides a long list of various Italian surnames, and of the city or town that they live in.
http://gens.labo.net/it/cognomi/genera.html
Website related with Telefónica. Here it is possible to search in all of Italy for a specific surname and locate it.
http://www.paginebianche.it/index.html
italian phone list
http://www.imigrantesitalianos.com.br/
This web site is very similar to the previous one, with links of relevant investigations.
http://www.projetoimigrantes.com.br/
This website contains a list of all the passengers that come into Brazil. It does contain useful information, however if does have to be payed for, but it is not expensive.