The following websites may be useful in researching your Irish family history:
Irish Genealogical Society International
Public Record Office of Northern Ireland
The National Archives of Ireland
Irish Genealogy.ie ( includes free acces to records for births from 1864 to 1918, deaths from 1878 to 1968, and marriages from 1864 to 1943)
Catholic Parish Records at the NLI
Ellis Island (database of ship passenger arrivals at Ellis Island from 1892 - forward)
Family Search (LDS / Utah Genealogical Society)