Thank you for your message.
The reality of finding documentation pertaining to births/baptisms/marriages/deaths in Ireland prior to 1800 ? particularly in rural areas ? is that they simply may not exist. Some registers for urban areas pre-dating 1800 may exist ? though often these can be fragmented- as there was an increased need in cities or larger towns to document the population. Please also note that the Church of Ireland was the official church of the country and therefore the bulk of information that does survive for earlier periods is often from these registers.
Church of Ireland parish registers for the period up to 1870-are public records. Registers are available for about one third of the parishes, however many were destroyed in the Public Records Office in Dublin in 1922. Most are still held by the local clergy, although some are in the National Archives of Ireland and others are in the Representative Church Body Library in Dublin. A list of all surviving registers is available in the National Archives. http://ireland.anglican.org/about/42 and http://www.nationalarchives.ie/. The Anglican Record Project is has created an index to their records: http://ireland.anglican.org/cmsfiles/pdf/AboutUs/library/AngRecord/bunclodyunionindex.pdf
Some sites which may be of interest to you are:
The National Archives of Ireland http://www.nationalarchives.ie/genealogy1/genealogy-records/introduction/
The National Library of Ireland http://www.nli.ie/en/family-history-introduction.aspx
The National Archives UK ? genealogy search: http://www.nationalarchives.gov.uk/records/looking-for-person/
British parliamentary papers on Ireland can be found at: http://eppi.dippam.ac.uk/documents/9824/eppi_pages/215093
Remember to post as much information as you can with regard to the people you are researching. The more information you post, the more likely it is that one of our volunteers will be able to advise or assist you. Also include information concerning which sources you may have already used so others may further your search.