My information is a bit dated. My wife and I went there on our honeymoon. Next year is our 15th anniversary, so we are considering going back.
We stayed in B&Bs the entire time and loved it. We also (for the first night) stayed at Dromoland (spelling?) Castle not too far north of Limerick.
Driving on left was an interesting experience, but not too difficult (except for going onto the left side of the median when entering a divided highway!). It was nearly impossible to make myself turn onto the wrong side of the road!
We used a B&B guide we bought in the States, then we would drive until early afternoon. Look on the map to see where we might end up by the end of the day, and then start calling around for rooms. We had no trouble getting rooms every night for reasonable rates. The food was fabulous, and almost too much. By the end of our stay, we were seeking out pubs to eat something a little smaller than the meals served at the B&Bs.
You also meet a lot of people that way. We met a lot of people who were vacationing from the continent (mostly Germany).
The Guinness is 1000x better there than here (in the US). Especially at the brewery in Dublin. For any stout drinker, it is the mecca. And after the tour you get to sample some of the nectar of the gods. It was great!
Also, I would recommend the tour at Waterford crystal. It is truely an artform which must be seen to be appreciated.
If we had to do it over again, we would not try to cover so much ground. We went from Limerick, up to Galway, then back down around the ring of Kerry, across to Cork, then to Waterford, up to Dublin and back across to Limerick. All in one week. Hey, we were kids and didn’t know any better!
It was a fantastic time. Watch for the sheep crossing the road.
There was also a lot of hitch hikers. Most people there did not have a car, so we picked up a number of people and gave them lifts. It was a great way to learn more about the local places (especially the best pubs). This was before we had discovered Irish music, so we did not even know what we were missing.
The pace was much slower there (a good thing!). Most people don’t get more than a few miles from home, so meeting someone from half way around the world is a treat for them as well. Be careful not to make too big a thing about it, as that would be rude.
Have fun!