Just to clear up some confusion about Irish records-
1) civil registration of births, deaths and Catholic marriages started in 1864 (from 1845 for other marriages). Before these dates there will be no certificates and you'll need to see if any church records exist (many do not go back before mid-1800s)
2) to find church records you'll need to know both the family's religion (Catholic, Church of Ireland, Presbyterian, etc.) and where they lived (parish if not actual townland)
There are lots of Irish resources now online (PRONI have microfilmed copies of many church records but not the original records).
Introduction to Irish Records and
My Ancestor came from Ireland - where do I start?.
