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@Animal02 says, get a car and do your own thing. I really dislike travel packages where you travel in a group since other people tend to go slow or want to ship or do other things than my wife and I would like to do (walk several miles between meals and tour). If we find a place that looks good, it is really nice to just stop and have a carafe of wine. But package deals are really good if you want someone to take care of most things for you. I like researching areas and figuring things out so the preparation is enjoyable to me.
When my wife and I have traveled in Italy and France, we use the trains since the system is so good and we like staying in smaller cities like Sienna. I don't think the trains would be as good for Ireland as it is so rural so I'd get a car. We book hotels / B&Bs in advance from
http://www.hotels.com/search.do?resolved-location=CITY:691513:UNKNOWN:UNKNOWN&destination-id=691513&q-destination=Dublin, Ireland&q-localised-check-in=09/01/15&q-localised-check-out=09/02/15&q-rooms=1&q-room-0-adults=2&q-room-0-children=0
Generally we will book and pay well in advance and get really great rates. It has worked out since we haven't had to skip places we booked. The most important thing is to carefully read the reviews and make sure you are comfortable with the level of amenities and also that the reviews appear to be from real customers. Once we get to an area, we like to ask at the hotel for local food recommendations.