hi tk...you already have a lot more info than i did when i started my search. being as your grandparents came to this country to live you can obtain marriage licenses (if they married in the usa), death certificates, cemetary documents, naturalization/immigration papers. as for your great grand parents you have good info to start with. you can write to the town the family was from to request a family certificate. this is where i would suggest you begin as you'll get your great granparents with their parents possibly their parents as well and siblings of the first family with dates of birth and death if they died in the same town. if you should need birth or marriage or death records a different office in the same town holds those archives. you would have to write in italian and it does cost a small fee. there is a site i can send you to guide you. i used it and believe me it works....i got 8 out 9 responses for different info.