Galway on the west coast is a great place. Friendly to travelers, good arts seen, great local music seen, lot of European bands pass through, great pubs.
Believe it or not, but Belfast in N. Ireland has a pretty good scene to it – it has really begun to blossom the past few years. I would recommend the Menagerie on the weekends for good music/fun.
Port Rush in the North is pretty touristy but they have Kelly’s the biggest club in Ireland that has something for everyone (lot of youngin’s though – but something to experience). The club has been there sense the 1930’s. Also Portrush is a popular skate town if ya’ like that & it is a beautiful seaside town with one of the best surf breaks in Ireland.
Donegal has a bunch to do/see/experience.
Sligo is another city w/ a lot to offer.

I would suggest going to Northern Ireland also, neat places to visit are Giants Causeway and Carrick-a-rede rope bridge. Staying up on the north sea is just amazing! Belfast is interesting to learn about all of the political/religious strife.

Hi, for expert travel advice on Ireland, check out www.irelandyes.com. Michelle Erdvig is an Ireland travel expert and can answer all of your questions and more. a great Ireland messageboard site. Have fun on your trip -the irish people are awesome. Greg