Researching my maternal background was relatively easy. Ancestors had published a "Peck" book that went back to 1637 and the arrival of Henry Peck on the ship "Hector" out of England. Furthur research at the GRO in Kew, England, indicated that Henry was from Norfolk, England.
My paternal ancestory, was a bit more challenging. I was able to trace my Great Grandfather Arthur McDonald through his death certificate that was in the vital statistics in Danbury, CT. While that did not provide the place in Ireland that his parents came from, it did provide their names, including the maiden name of his father's wife. Just before visiting Ireland to do some research, I contacted/paid a reputable genealogical organization in Ireland to do some preliminary research for me. It paid off big time! She was able to pinpoint the townland in western County Clare where my GGF had lived on his family farm. When I visited the townland, I was able to find and visit with living relatives! We now are sharing information and photos, etc. I enjoy my extended family.