Not sure which university, but I'm almost certain it is in Dublin.
Hmmm.
I'm in Galway, which is the far side of the country, and I don't really spend that much time in Dublin - I know my way around the city centre, but that's about it really.
You could dry PMing Demented_Elf or Araquael on RPG.net - Araquael is in Canada ATM (I think), but iirc he went to uni in Dublin, and Demented_Elf is in Dublin at the mo. There are a couple of other Irish posters over at TBP as well.
As far as tips:
If your friend is going to DCU or UCD, both have some on-campus accommodation, and they usually reserve some space for foreign students. It's worth contacting the Uni administration about that kind of thing. It's probably not cheap, unfortunately, but nothing in Dublin is...