As with other searches, the greatest success is usually found in researching the smallest unit. In Italy, if you know the region or town, you are more likely to be able to find the Catholic church. It is far more likely to have a record of who served there (or who may be buried in the local churchyard) than the central agencies of the Vatican would. That is true of the USA as well. I have also found help by consulting the information centers run by foreign governments in large cities in the USA. They have a wealth of information geared to tourism which may well include maps and other information about specific areas. Their job is to encourage you to visit, and I find most of these agencies pleasant to deal with. They are listed in phone books of metropolitan areas like New York. In the USA, there are national and local registers of parishes and priests. Your local church should have copies. Also, when a parish celebrates a major anniversary--fifty or one hundred years--they are quite likely to publish a commemorative booklet that will usually include a list of priests who served during the period. Consult your local church for information on parishes in the area you are researching. Happy hunting. Grace