Hi Damien, I've drank in Limerick a few times over the years and there really is no good place for a diverse whiskey selection.
The only place I remember seeing anything out of the Usual was the Savoy hotel bar and that was just Laphroaig 10yo, HP 12yo and a few other Single Malt Scotch as well as a decent few premium Irish. This seems to be the norm for most well stocked bars in Ireland, however you could not call them Whiskey bars.
For pubs in Limerick you have
Clohessy's sports bar which is a great place to watch sport and a good place to start your day.
Flannery's which is associated to Jerry Flannery's family so a big Rugger spot and is usually fairly packed but not a bad spot if you don't mind crowds.
Then you have popular places like AU Bars (known locally as O bars
) for the in people. Nancy Blakes near the latin quarter which is more an old style bar with loads of different rooms and the side ally is annexed and covered so you can have a pint and smoke there and often there is live music in this area too. Try the Latin Quarter for pubs in general.
Also Dolans on the Doc Road for live music but look it up first to see what's on and get a taxi to and from as it is a bit out of the way in a quite area and I would not personally like to walk it if alone. Not very far from the centre at the same time so if in a crowd ye should be fine to walk.