Hope you will enjoy you visit to Ireland but at the moment it's cold and wet.
Civil registration of births, deaths and Catholic marriages began 1864 (from 1845 for Protestant marriages).
For earlier research you need to know the family's religion (not just Protestant) and where they lived in order to find church records (if they still exist).
Many early gravestones don't survive (if there was even one in the first place) and also keep in mind that many Presbyterians are buried in Church of Ireland graveyards (and not always recorded in the burial register) so don't assume your relatives were C.of I. if you find them in the local Parish graveyard.
Church of Ireland website:
www.ireland.anglican.org/index.php?do=information.diocesesNote: there is a Cappagh Parish Church
Presbyterian:
www.presbyterianireland.orgOf course there were also Methodists, Congregationalists, Baptists, Quakers, etc. in Ireland.
Killyclogher is the name of a townland (300 acres). Barony- Strabane Upper. Civil Parish-
Cappagh. Poor law Union- Omagh. See
www.thecore.com/seanruad to find townlands and parishes.