There are some PGN files amongst the Downloads but the main way of searching for and playing over the games of (mostly) Irish players is via the Games page. (Apologies for the delay, a game viewer is not available yet but one should be in place before the end of 2014.)
Like the previous version of this website, a ZIP-compressed PGN file of all games in the collection is available for anyone to download, but unlike the old site, there are a couple of new ways to download PGN data for members who are signed in (see Annual Subscriptions and Membership of the ICU and Login Accounts for the ICU Websites).
See also Upload PGN Games for administrators.
Click the Download PGN Database link on the Games page.
This file is regenerated once per day early in the morning if there have been any updates to the games collection during the previous day. There will normally be some information next to the link about how many games the file contains and when the last update to the collection was at the time the file was generated.
This will download an uncompressed PGN file containing that one game to your computer.
This will download an uncompressed PGN file containing all the games in the result set to your computer.
If you need more than 1000 games, download the entire collection (see above) and use your favourite database program for searching.