Following Elwyn's advice, the Griffith Valuation 1847-1864 depending on county:
www.askaboutireland.ie43 in Galway, 4 Mayo, 12 Offaly, 3 Longford, 4 Meath, 1 Westmeath.
www.genealogy.nationalarchives.ie Tithe Applotments: 1823-1837 not all parishes in a county and not all counties. Originals at the National Archives, Dublin.
www.census.nationalarchives.ie 1901/1911 Census and this year the addition of fragments from
early census 1821-1851 that survived the Four Courts Fire 1922.
www.rootsireland.ie parish records usually to 1899, prior subject to survival
www.familysearch.org civil registration started 1864 and these records in Ireland go to the 1950's.
A person could have a birth date, a baptism/christening date and after 1864 a civil registration
quarter, usually based on the Poor Law Union which then became the Civil Registration Districts.
Without a first name or other clues, not going to look through the above locations. Once you have the right location, I can look further through some other sources.
Annette Code