When you say histories I assume you mean you want to trace your family genealogy and at the same time locate current relatives in GUARDIA LOMBARDI Postale 83040.
Go to www.paginebianche.it and insert the D;Antonio surname in the first line. Since there are no D'Antonio surnames there go to the third line and put in AV (for avellino province) where there are 26 listings both commercial and resiendetial whichmay be of interest to you. If you wish to trace your family you can either go two ways. One is to write to the town and rerquest birth,marriage and death certificates if you know the full names and year of birth and the second option is to go to the nearest family history library of the Mormon church and rent out the microfilm of civil records for Guardia Lombardi which date from 1809 to 1910 and then you know that your parents or grandparents were alive on or about 1910 then you can trace their parents and children all the way back to 1809 and research your entire family. Lots of luck. Peter