I have written before about the excellent Irish in the American Civil War website. Last week, the author, Damian Shiels, wrote a lengthy piece titled, "How to Find American Civil War Veterans from Irish Counties: A Case Study of Matthew Dooley, Roscrea [Co. Tipperary]."
In this article, Damian uses the example of his research on Matthew Dooley to highlight many resources of relevance when it comes to Civil War research. There is a New York State angle to this research too. This makes the article even more useful as the vast majority of Irish in the Civil War were from the state of New York.
It is a must read if you have Civil War ancestors and are looking for your townland of origin.