Claddagh Records in Cecilia Street, Dublin, is the best place in the world to get traditional Irish music. They have an email address, but I'm not sure if it's crl@iol.ie or crl@indigo.ie - and I think they have a website somewhere.Take a look at the Ceolas site, anyway - you'll find recordings of sean-nós which you can listen to if you have Real Audio plugins installed.
And finally, you should join the Gaeilge-B listserv for Irish language learners.
Adh mhór leat!