Some information that may help in getting to the conference:
The two major airports that may be of use are Dublin and Shannon. Dublin has, by far, the most connections and there are good bus services from Dublin airport to Limerick. Skyscanner is a good starting point when looking to see what carriers you may be able to use.
The Conference and Sports Bureau website site gives some info that may be of use, although some appears to be out of date.
Dublin Coach provide a service from Dublin Airport to the university campus in Limerick. The route is the M7. To me, this looks like the best option.
JJ Kavanagh, a little more expensive, also cover this route.
Bus Eireann also provide a coach service.
For those who prefer to drive, I can recommend http://www.hamills.com/
If you decide to use Ann's services, email her on email@example.com and mention DNN Connect. My only connection to Ann is that I use her any time I need to rent a car and have been doing so successfully for many years.