It's so exciting that you discovered your Irish roots just before your trip next month, and I'd love to see what I can do to point you in the right direction for more information about your family tree. :)
It's wonderful that you already were able to find your ancestors this far back! Are you trying to find out more about Patrick and Margaret's parents? Before 1864 records were kept in the form of church and parish records; while some of these have regrettably been lost over the years, all the surviving records have been sorted into county-based genealogical centres
Clogherhead is located in County Louth, and you can get in touch with the centre
there, as well as make an appointment for your visit to do more research.
Another great place for research, as well as interesting information, is EPIC
, the Irish Emigration Museum in Dublin. Are you planning on visiting Dublin while you're here as well?