Depends what county or city. Here are the ones I know about.
Cambria County PA
http://blacklick2.000webhostapp.com/interest.htmlObituary indexes to the Johnstown Tribune and other papers are at the bottom of the page.
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Mahoning Co Ohio
http://www.mahoningcountychapterogs.org/Information.aspxCoroners Inquests, 1883-1908
Some other early records.
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New York City
http://www.italiangen.org/records-search/I haven't looked for deaths here, usually marriages.
Familysearch finds early birth records in Cleveland, Ohio. Sometimes there are two or three results for each birth. Click on all of them. Look for an image of "Return of a Birth". That is the form the midwife or doctor filled out and sent to the city. I have actually found Irish county of origins twice or three times on these forms, but never on the city or county copies. There isn't always one on familysearch for every birth, however.
Same with Cuyahoga Co marriage and death records at familysearch, as with every location, really. If there are two, the one from the city came first, then the county made a copy. Sometimes you lose a little detail in the copying.
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I have also seen items in City Directories that noted that the occupant had died on a certain date in the previous year. I don't remember what city though, but the chances are good that it was Cleveland, Ohio, or Boston Massachusetts, since that is where I have looked at the most city directories.
And sometimes the widow will be listed starting the year after a man dies as "widow of".
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There are probably other localized databases as well for other counties, but the ones above are the localities I have researched in.
Google is your friend. Also the old Genweb sites for counties. Some are good for telling you available resources, and some aren't.
A local library webpage might help, or an email to the research librarian, asking for such sites.
What are your Irish names? If they are in Cleveland especially, I might have seen some of them.