How can I go about finding birth certificates out of Palermo Italy?

My great grandmother and grand father came over from Palermo could you help me im tring to find out info on Milazzo's

I am new to this but just tring to find out some family history,Im tring to find out a lil more on why The Leones droped the E off the end when they came to the USA,around 1900 in New Orleans,La also looking to see any info on Malazzo's and Sanangelos..Thank You.