The following are a list of sites useful for researching Irish ancestors
Websites for Irish Research
The Public Record Office of Northern Ireland is the official site for Northern Ireland records
Irish Genealogy is a key site for researching all Irish Births, Deaths, Marriages.
http://www.genealogy.nationalarchives.ie/ - British national Archives
https://www.ancestryireland.com/
https://www.irelandxo.com/ireland-xo/history-and-genealogy - Ireland Reaching out
https://www.irishnewsarchive.com/ Newspaper archives
https://www.emeraldancestors.com/ Good Northern Ireland records
http://www.failteromhat.com/ free site for Eire
https://aad.archives.gov National Archives Famine Collection
http://www.rootsweb.ancestry.com/~fianna/
http://www.irishwarmemorials.ie/ - Irish war memorials
https://infowanted.bc.edu/ - searchable database from Boston for finding Irish immigrants
http://www.irishancestors.ie/resources/unique-resources/the-irish-genealogist/
https://www.irelandxo.com/ireland-xo/history-and-genealogy
http://www.irishtimes.com/ancestor/surname/index.cfm?fuseaction=Go.&Surname=Semple&UserID=
Irish Surnames - http://www.irishtimes.com/ancestor/surname/index.cfm?fuseaction=Go.&Surname=Semple&UserID=
http://www.irelandxo.com - Ireland Reaching out forums
National Library of Ireland - Directories
Grifiiths Evaluation Rolls - Not easy to search but one of the best Irish sources
Irish Almanac - a Database on everything Irish
Directories and much more - Shane Wilson's fabulous database on a wide assortment of Irish genealogy resources.
THE LIST of CHURCH OF IRELAND PARISH REGISTERS is a list of parishes and where their records are held
The Meithal Community Placename Collection: for placenames that may not be townlands after all