Without dates searching newspapers for possible death notices would be very time consuming. Some commercial website allow newspaper searches by keyword which might help. Deaths would be including in civil records, which can be searched up to 1958 using the FamilySearch Index, although searches will not be easy for common surnames.
Two websites which cover Irish newspapers would be the Irish Times Archive which goes back to 1859, and IrishNewsArchive which includes a number of Irish newspapers including Freeman's Journal from 1763 up to 1924 (with a few gaps), and also the Irish Independent from the start of it's publication in 1905.
Records for Glasnevin, one of Dublin's major cemeteries, are available on a pay-website, and some other details are available on free websites (mostly from Memorial Inscriptions rather than burial records) - see :
Dublin GraveyardsShane