I have been doing a family history for at least three years.
In relation to birth etc...details i have been using the Limerick heritage Centre. There are a number of these around the country but you need to have some basic info first. I also taped my Dad during his life...
Regarding the US, a Christopher Carroll went to the uS in the early 20th century. He was son of Daniel, who in turn was the youngest son of Daniel whereas my Bernard was the eldest. He went to Boston andI believe his brother Patrick went with him. I found them so to speak in American census material on the internet - I think 1920...I don't know who or where their descendants are though most likely there are some out there. There could have been other emigrants but don't know of any more on the Carroll side. My grandfather Carroll died when his children were young - hence very little ancestral memory re the Carrolls.
If you have other info, you might email me on Cunniffe@iol.ie