Firstly and most recently, the National Library of Scotland have added Ordnance Survey Ireland - Six-inch, 1829-1842 maps to their freely available cartographical collection. You may find it easier to use the simple functionality on this website to initially view the maps, but I do recommend that you progress on to mastering the OSI's own Irish Townland and Historic Map Viewer. I've put together a page of instructions for you, which you can access here.
Secondly, John Grenham has taken a step closer to creating my kind of "catalogue". He updated his civil parish maps in July of this year by integrating them with the townlands data available from Open Street Map to create some beautiful multi-coloured parish-townland maps. He has now worked some more magic by creating links from these maps to the huge wealth of information about records he has elsewhere on his website. Take a gander at his joyful blog piece - "A circus-full of maps" - to learn more. Now if only he (and maybe Shane Wilson?) could find a way of pinning all the churches, graveyards, schools, workhouses etc. on to those same maps, with links to the available records, then we would be getting closer to my initial dream of a whole new way of exploring past landscapes.
Seriously, it is when you see wonderful innovations that knowledgeable genealogists are making to support us better on our quest that you get more and more frustrated with the paltry map offerings the we have to put up with from the family history software vendors. However, that rant ought to be the subject of another blog ...