My mother was an Ellerker. She lives in the village of Everthorpe which is only a couple of mles from Ellerker village. In Ellerker village there is a house called Ebenezer House and my g g g grandfather was Ebenezer Ellerker. He owned a pawn shop which is now in York castle museum. As you say Ellerker is not a very common name and i would lke to find out more information if you would be able to help. I also believe that the Ellerker chapel at Rowley Manor fits in. Thank you.