There are plenty of choices of accommodation in Ireland.
From 5 star deluxe hotels , cheap hostels , self catering cottages , Bed and Breakfasts and Guesthouses. All budgets and tastes are catered for.
You can search for vacancies and book accommodation online on the excellent Accommodation Ireland site. Search for hotels , self catering, bed and breakfast in every county in Ireland . All accommodation on the site is Tourist Board ( Bord Failte) registered. Check Accommodation Available Here

For families - self catering accommodation is probably the best for flexibility and value for money. Sometimes known in the USA as rentals - a self catering house or cottage allows you to come and go as you please. There will be all the amenities and fittings that you would expect to find in a family home - cooking facilities and crockery etc. With self catering you can eat what you want - when ever you want. Of course you will probably eat out a lot - but the ability to have breakfast or a snack whenever you want is much easier than hotel accommodation - especially with kids. (Unless money is not a problem for you).
Hostels are a good option for younger single travellers - less formal than a guesthouse or hotel with more freedom to do your own thing and mix with like minded people. If you want a quiet nights sleep though - a hostel might not be the best place for you.

B&B - Bed and breakfast - is a declining but excellent type of accommodation in Ireland. B&B is provided in the owners own house - you get a bedroom and breakfast. If you like the personal touch and the chance to chat with your host and experience Irish hospitality - then B&B is the best option for you. It is a good idea if you are touring the country to book a few days ahead to ensure you get accommodation. The large breakfasts will ensure you won't need to eat again till evening. Some BandB will provide dinners on request.

Hotels in Ireland are on the increase due to tax reliefs. The large number of hotel rooms has meant a reduction in prices in some places. Hotels can be very expensive for large families - but for couples they can be reasonably priced. Hotels can be the best option in larger towns and cities - being centrally located. Dublin Hotels can get booked up well in advance - so book early.