« Reply #4 on: Thursday 04 July 13 19:23 BST (UK) »
The surname search in the Ancestors section of the Irish Times website suggests Louth, Monaghan and Mayo were the counties with most McGoughs in the years the Griffith's Valuation was taken, 1847-1864. A search on rootsireland.ie in those counties might be a place to start.
O'Brien, Keogh, Byrne, Cuffe, Kelly, White, Burke, Blosset, Evans, Hetherington, Hosey, Williams, Wright, Comerford, Carey, McKeon, Litton, O'Reilly, O'Toole, Nugent, Traynor, Broughall.