As Gurley/Gourley is a scottish name I recommend that you contact the Monreagh Ulster Scots Heritage and Education Centre. They may be able to help you and have many local contacts. Their website address is http://www.monreaghulsterscotscentre.com/
Also another website that is very helpful is Doengal Genealogy Resourcs - http://freepages.genealogy.rootsweb.ancestry.com/~donegal/
I wish you the best of luck with your research.