Grafton St. in the City Centre has a Brown Thomas that is likely to carry some high-end shoes and suits. As far as smaller tailors, etc., I am not sure. I have visited Dublin many-a-times and must say that is has a quite poor shopping scene as larger European cities go. Either way, all shopping is in City Centre: St. Stephen's Green, Jarvis Street, Grafton St., Temple Bar, etc. etc. all within walking distance from each other. If worse comes to worse, inquire with someone at Brown Thomas, they are very knowledgeable and will surely be able to lead you in the right direction.