If you're planning to visit 5 of Ireland's most popular cities- Dublin, Cork, Killarney, Galway and Limerick- you'll want to check out the free download-able guides from ArrivalGuides.com.
The guides list tips on what to do, where to stay, places to eat and shop as well as vital information like transportation, city size and weather.
Though the guides are far from complete, from what I see they are a very nice overview and introduction to prepare you for your visit. Besides, you can't beat free.
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