Hi Wesley,
Do you know much about their emigration? Dates, the reason why they left, etc.? Generally more information was given at the port of arrival rather than the port of departure. If you knew which city they arrived at (e.g. Liverpool, Castle Garden, Ellis Island etc...), this could be a good place to find more information. A few sites to try for emmigrant information are: http://www.castlegarden.org/ http://www.nationalarchives.gov.uk/records/ http://www.ellisisland.org/ http://www.proni.gov.uk/
You could try checking the land records called the Tithe Applotment Books (1823-38) or the later Griffith's Valuation (1848-64). The Tithe Applotment Books (1823-38): Microfilm copies of the books for all of Ireland are available at the National Archives of Ireland (NAI) http://www.nationalarchives.ie/genealogy1/genealogy-records/tithe-applotment-books-and-the-primary-griffith-valuation/ or the Church of Latter Day Saints (LDS) https://familysearch.org/. Griffith's is freely available here: www.askaboutireland.com or here: www.failteromhat.com Failte Romhat has lots of other useful links you could try looking at.
Civil registration records are available from the General Register Office (GRO). These start from 1864. You can access the website here: http://www.groireland.ie/research.htm . Valuations office in Dublin (http://www.valoff.ie) will have a record of the land registry from 1855 to modern times. This will assist in seeing what happened to any land the family may have owned (as it usually passed on to a relation).
Church records may also be of assistance to you. Church of Ireland parish registers for the period up to 1870 are public records. Registers are available for about one third of the parishes, however many were destroyed in the Public Records Office in Dublin in 1922. Most are still held by the local clergy, although some are in the National Archives of Ireland and others are in the Representative Church Body Library in Dublin. A list of all surviving registers is available in the National Archives. http://ireland.anglican.org/about/42 and http://www.nationalarchives.ie/. For Catholic records, information regarding what may be available in your area can be found at http://www.nli.ie/en/parish-register.aspx . Some of the Catholic records are held locally. If you have any difficulty, it may be worth while to contact the local parish offices for assistance. Contact information for Ardfert parish can be found here: http://www.dioceseofkerry.ie/parish.php?parish=Ardfert&sec=priests
I wish you the best of luck with your search.
Please make sure you link anyone else in your family who is interested in their Irish heritage to our site - and indeed anyone else you know of Irish heritage.
Kind regards,
Genealogy Support
Ireland Reaching Out