GRONI, the General Register Office Northern Ireland is the best place to order your BMD certifficates from Northern Ireland. It costs 8 pounds each for a Birth ,Marriage and Death certifficate.
Registration indexes held by GRONI
Births registered in Northern Ireland from 1 January 1864
Adoptions recorded in the Adopted Children Register Northern Ireland from 1 January 1931
Deaths registered in Northern Ireland from 1 January 1864
Registered Non-Roman Catholic marriages from 1 April 1845 and all registered marriages from 1 January 1864
Civil Partnerships registered in Northern Ireland from 5 December 2005
World War II death indexes from 1939 to 1945.