Hi Steve,
Thank you for your message.
Do you have a more specific place of origin in Westmeath? Most Irish record sources- church records, land records, census records- are based on specific locations. Until you know a specific location within Ireland, preferably a parish or placename, it may be difficult to do anything more with these records.
Have you tried looking into their emigration? Generally more information was given at the port of arrival rather than that of departure, so this may be a place to find more information and possibly even an exact place of origin! For immigration records in the US check the US National Archives at the following link:
http://www.archives.gov/research/immigration/
As they were in the US by 1852 they were most likely processed at Castlegarden. You can search their database here:
http://www.castlegarden.org/
You could also try searching for their parents in the land records pertaining to Ireland in the 19th century. Although these do not offer any genealogical information they can be used to tie a person to a specific place. There are two:
The Tithe Applotment Boos (1823-1838) found at http://titheapplotmentbooks.nationalarchives.ie/search/tab/home.jsp
and Griffith?s Valuation (1848-1864) found at http://www.askaboutireland.ie/griffith-valuation/
Another good website is https://familysearch.org/ . This is a huge database of genealogical records compiled by the Church of the Latter Day Saints. It includes marriage/death/birth registers for Ireland ranging from pre-11871 to 1959. Although these records are incomplete you may be lucky and find a record belonging to someone in the family, which will give you a parish name also.
Some other websites which you may find useful 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
The Public Records Office of Northern Ireland http://www.proni.gov.uk/index/family_history.htm
Genealogy Links: http://www.genealogylinks.net/uk/ireland/westmeath/index.html
Alternatively, you could contact the heritage centre in Westmeath for assistance- a fee may apply. Here are their contact details:
Dun na Si Heritage Centre,
Knockdomney,
Moate,
Co. Westmeath.
Phone: +353 (0) 90 648 1183 Email: dunnasimoate@eircom.net
I hope that this is helpful. Remember to post any new information you find. 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.
Kind regards,
Genealogy Support