THESE RECORDS ARE IN LATIN, VERY, VERY FEW ARE IN ITALIAN!
For example: Giuseppe is, therefore, Joseph/Josephi/Josephus and since there are no J's in Latin, you will find them under I's. Giovanni is Joannes/Jo~es Gerolamo is Heironymus and under Hs Georgio is Giorgius and under Gs Filippo is Philippo/Ph~o and under Ps
Some of these volumes had newer indexing and transcriptions done for them by the Church. There are some done in the mid 1800s, some around 1908-1930s. These are really nice, but as with all things re-written, there are errors, and it is best to look at the original, as well.
Some of these volumes have no index, others have as many as three. For those that have the newer index and transcriptions, you can find the original entry in those volumes that have no index at all. Just narrow down your way through the dates in a volume that you have found in the newer transcription.
I hope this makes your research a bit less frustrating. I have had extraordinary fortune with this set of documents and I hope you will have the same.
Oh, and just to keep life interesting, every once in a while, you may find a missing page or two, where of course one of your ancestors should be, and sometimes several years will be gone. There are a lot of pages duplicated because of crooked copying, so account for that on your page numbers. Don't think I am complaining, as this has been a gold mine of information for me, and am surprised some of these records are in such good condition for their years! Thank you Family Search for making them available! I will post the remainder of my info in responses to this.
Battesimi/Baptisms These are generally alphabetized by the father's First name. Father and mother, then child, then page. There are a couple of books that decided to experiment? with turning some of the entries around, (child, then father, mother, page), but they are few.
1566-1617 This has a new index and transcription of the old records. 1577-1596 No index Use dates found in indexed years. 1598-1647 No index " " " " " " 1618-1655 New index/transcription 1647-1664 No index 1656-1696 New Index/transcription Missing years 1685-1691 in many names 1665-1685 No Index Nov 1665 at Img-5, Jan 1679 at Img-200 1692-1704 Index in Front and at Image 249 1705-1711 Index in Front 1711-1721 Index in Front 1721-1728 Index in Front 1728-1738 Index in Front 1738-1752 Index in Front 1753-1762 Index in Front and @ Img 255 1762-1768 Index in Front and @ 220 1767-1773 No index 1773-1779 Index in Front 1780-1788 Index in Front and @ Img 498 1788-1793 Index in Front 1793-1799 Index in Front 1799-1815 Index in Front and @ Img 360 1815-1835 Index in Front and @ Img 151(1825+) 1836-1857 Index in Front and @ Imgs 302 and 546 1858-1865 Index in Front 1865-1876 Index in Front 1877-1884 Index in Front and @ Img 291 1885-1891 Index in Front 1891-1892 Index starts @ Img 49 1892-1911 Index in Front and @Img 315
Matrimoni/Marriage These are alphabetized by Groom's First name. 1579-1686 Index in front 1687-1702 Newer Index in front, and @ Img 104 are orig records from 15-1600s Marriages For reference, Img 156 is the beginning of Sept 1641 1702-1713 Index in front 1713-1719 No index 1719-1746 Index in front and @ Img 251 1746-1774 Index in front and @ Img 265 1774-1779 Index in front 1779-1791 No index 1791-1803 Index in front 1803-1819 Index in front 1825-1840 Index in front for 1819-25 and @ 32 for 1825-40 1841-1865 Index in front and @ Img 251 1866-1870 Index in front and @ Img 177 1881-1911 Index in front and @ Img 266 and 429 Marriages for 1871-81 are in Vol 1866-70
Morti/Deaths These are alphabetized by decedent's First name. But, in the case of women, it may follow with their maiden name or, if they were widowed, by their husband's surname. So, check all possibilities. They may also be shown with their father/parents, as in the case of children. Beware of 2nd marriages. You may find a name that fits the time frame, but shows another spouse. Check it out, as most of the time the record will show a previous spouse. 1648-1700 No index 1701-1726 Index in front 1726-1751 Index in front and @ Img 188 1735-1754 Mostly index 1751-1783 Index in front and @ Imgs 230-298 and 667-739 1754-1758 No index 1770-1786 Index in front (some sort of acct'g pages in back) 1782-1795 No index 1786-1837 Index in front and @ Img 316-336 and 546 @450 are more ?acct'g entries 1795-1813 Index in front and @ Img 374("I"s) 1813-1844 Index in front and @ Img 137 1837-1846 No index and appears to be babies and youth 1845-1850 Index in front 1847-1884 Index in front and @ Img 181 1849-1865 No index 1865-1892 Index in front and @ Img 252 1884-1910 Index in front (starts with I and then on to the rest) and @ Img 128 and 234 1892-1911 Index in front and @ Img 183 and 227