If you are writing a pre-famine family history, or simply wanting to know what life was like in a particular area, then The Parliamentary Gazetteer of Ireland (1844) may be what you are looking for. This is a ten volume set arranged alphabetically. This work is found several places online, so it is best to Google the title of the book and see which database you want to consult.
This work is similar in scope to the two volume Topographical Dictionary of Ireland (1837): www.libraryireland.com/topog/index.php by Samuel Lewis, which I have already blogged about. The two sources together provide you with an excellent pre-Famine view of Ireland.
The gazetteer is written from the government point of view, so a parish entry will mean civil parish. However, Roman Catholic history and statistics will be listed under the civil parish. There are entries for counties, parishes, islands, towns and considerable villages, baronies, principal mountains, bays, all fishing harbors, all rivers, principal lakes, chief mines and mineral districts, on all villages which contain at least twenty houses, and hundreds of others which contain fewer, and principal rural antiquities to name some of the topics covered. This remains a true encyclopedia of pre-Famine Ireland. What is not listed are histories on individual townlands.
The entries all sorts of statistics taken from the 1831 and 1841 censuses. This in itself can provide you with hard to find information from which to develop your narrative, if you are writing a family history or conducting historical research.
A breakdown of the volumes are as follows: Volume 1 (A-Arm), Volume 2 (Arm-Car), Volume 3 (Car-Cus), Volume 4 (Dal-Gal), Volume 5 (Gal-Kil), Volume 6 (Kil-Mag), Volume 7 (Mag-Rap), Volume 8 (Rap-Tib), Volume 9 (Tib-You), Volume 10 (You-Z and Index).