Where to purchase a SIM card in Dublin?

Go down Henry Street, it is a left, across from the Spire on O'Connell St. There are 2 malls and lots of small shops. Find a Cell phone store, go in and ask.

Not to hijack the thread, but...are there any good options in Dublin Airport?

We will be jumping on a bus or train and heading out to Galway. So if there's a shop in the airport, that would be ideal (at least for us).

I bought a sim card at the SPAR store, terminal 2, just after we picked up the luggage from the carousel. Just ask the clerk at the register. This was back in February. The card should work in all European countries because there is no longer a roaming issue.

Thanks, Carl.