Hi Genie,
You don't mention where you're living in the US or if you have access to a large college or university library.
I think one of the difficulties I've seen when researching emigrants from Ireland and Ulster during the Famine to the US is that Ulster Scots were already in great numbers there prior to the Famine and they were very helpful to the Ulster Scots Famine emigrants who arrived there with jobs, housing, etc.
There had been huge emigration from Ulster especially of Ulster Scots beginning in the 1700s primarily because of the British Penal Laws enacted then which forbade practicing any religion other than the Church of Ireland (Anglican) and denying people the rights to own land and vote if they were other religions. Then another wave after the failed Irish Rebellion of 1798 which included many Ulster Scots as leaders of the rebellion.
The Famine emigrants were considered in the US as a lower class or lower socio economic class than the Ulster Scots who were already there and so were classed in that lower economic group identified with the Famine and the Catholic religion. The Ulster Scots on the other hand separated themselves from the waves of Famine immigrants in that lower socio economic class.
Also many books have been written about the Famine emigrants and they were written in the late Twentieth Century (primarily in the run up to the Famine 150th anniversary commemoration beginning in the late 1980s and early 1990s) when the polarisation on religious grounds in Ireland became more cemented in the Twentieth Century especially after the Irish Free State and Northern Ireland were divided in 1922.
There was also a collective amnesia here in Ireland and in Ulster about the Famine. It was so horrific no one talked about it because it was absolutely so horrific. There wasn't any observance for the 100th anniversary here and if it wasn't for Cecil Woodham-Smith's groundbreaking book in 1962 "The Great Hunger" many people wouldn't even have known about it. But it took another nearly 30 years after her book for the topic to begin being scrutinised primarily among the descendants of those who emigrated to the US and who brought pressure to bear to acknowledge it. Even observances here if there are any are in conjunction primarily with current hunger in Africa so it's still a very difficult subject to deal with.
Thomas Gallagher who wrote Paddy's Lament was US based (Manhattan) and is since deceased. Many books about the Famine initially were by US authors or historians concentrating on Ireland and not the US. Here's a map of Ireland showing
Where did your ancestors emigrate to in the US? You might start with local histories for the area to see what the socio economic conditions were when they arrived and look at their US census information which should also help identify if they could read and write, if they were merchants or farmers, I believe the 1880 US Federal census includes savings and value of land for the emigrants. Local church histories may help too. Many Presbyterian churches there also have excellent church histories.
Where were your ancestors from in Counties Antrim and Down? If you look at the following link many areas of those counties suffered greatly during the Famine:
http://www.wesleyjohnston.com/users/ireland/past/famine/dist...It's only recently that even Famine graves are being identified in Northern Ireland, some information here and some history about the "collective amnesia":
http://www.ijai.supanet.com/vol1/tgf/famine.htmThere is one site in Belfast which has just recently even been identified as containing Famine graves I believe it's in the Cornmarket area in the City and Friar's Bush cemetery.
http://www.celtic-connection.com/2004/features/feat2004_11_0... The Ulster American Folk Park in Omagh, County Tyrone is working on Ulster emigration during the Famine:
http://www.folkpark.com/learning/schools/special_focus_visit...They're also compiling letters from emigrants home who left during the Famine.
The Ulster Museum also has a bibliography including books about the Ulster emigration during the Famine:
http://www.ulstermuseum.org.uk/ask-the-experts/13/Kerby Miller, a US based scholar and professor has done a large amount of research about the emigrants and Ireland. He had been a research fellow at Queens University in Belfast:
http://history.missouri.edu/people/miller.htmlAlso Library Ireland Ulster has some information:
http://booksulster.com/pipermail/libraryireland_booksulster....Pat