If you have found the specific locality of your Irish ancestor, and have reviewed the major record groups your next step is to look at what local records might be available. Although the oldest surviving complete census for Ireland is 1901, there are fragments of the 1821 - 1851 censuses that survived the fire. If you're lucky enough to have ancestors from Killeshandra Parish in County Cavan, the original returns for 1841 survived the fire. Even if your ancestors were early immigrants, most counties have records dating back to the early 1600s. These records may not be complete and may only cover one parish, but if it's the locality from which your ancestors emigrated, you may end up doing the happy dance.
To find these lists, look at John Grenham's Tracing Your Irish Ancestors, or James Ryan's Irish Records: sources for Family and Local History. You will also find some of the information online at the Irish Ancestors site of IrishTimes.com. If you're looking for early Scots-Irish ancestors, try Researching Scots-Irish Ancestors by William J. Roulston (these are all listed in the Books section of my website). Don't forget to also check out the Ireland Genealogy Projects website hosted by RootsWeb or the IrelandGenWeb Project. You never know what you might find there!
In the next week I'll be doing five lectures focused on Irish research. If you're in the New York City area, I'll be providing an Introduction to Irish Research at the New York Public Library on Wednesday, November 16th at 5:30 p.m. On Thursday, November 17th, beginning at 5:30, I'll be doing two lectures on Irish research at the New York Genealogical and Biographical Society: Locating Famine Emigrants Using Griffith’s Valuation and Sources for Irish Research. The lectures at the NYG&B require registration, so check the website. I'll be repeating the Sources for Irish Research at the Middlesex Genealogical Society Meeting in Darien, Connecticut on Saturday, November 19th at 2 p.m. and on Tuesday, November 22nd I'll be at the Irvington-on-Hudson Public Library providing an Introduction to Irish Research. If you are in the area, I hope you'll be able to attend one of these presentation.
After all of that, I'll be stuffing myself with turkey with my family in Connecticut!