Hi thanks for your message.
Have you tried searching thorugh Church records for any information on Murtagh? Most Roman Catholic records are held locally. One website which may be of use to you is the Irishtimes website. Here they give an overview of what records are available for specific parishes. To see what is available for Kilteevan follow this link:
http://www.irishtimes.com/ancestor/fuses/rcparishmaps/index.cfm?fuseaction=showidrecords&CityCounty=Roscommon&parish=Roscommon&churchid=564
For Church of Ireland Records check http://ireland.anglican.org/about/42 and http://www.nationalarchives.ie/.
You could also search for some record of him in the land records pertaining to Irland in the 19th century. There are two: The Tithe Applotment Books (1823-1838) and Griffith's Valuation (1848-1864). These can be searched here:
http://titheapplotmentbooks.nationalarchives.ie/search/tab/home.jsp
and
http://www.askaboutireland.ie/griffith-valuation/
Some other websites which may help you in your search are:
The National Archives of Ireland http://www.nationalarchives.ie/genealogy1/genealogy-records/introduction/
The National Library of Ireland http://www.nli.ie/en/family-history-introduction.aspx
and Family Search: https://familysearch.org/
I hope this helps. Remember to post as much information as you can with regard to the people you are researching. The more information you post, the more likely it is that one of our volunteers will be able to advise or assist you. Also include information concerning which sources you may have already used so others may further your search.
Please be patient - as our programme has only begun to rollout across the island of Ireland and volunteers in some areas may not yet be organized.
Kind regards,
Genealogy Support