I was rummaging around on the internet and found these, I am not sure what the normal retail price on these is but they seem to be a good price.
Great Southern Railway: An Irish Pictorial €10.73 including postage
http://www.bookdepository.com/Great-Southern-Railway-Murray/9780711031500
The Waterford, Limerick and Western Railway, Ernest Shepherd £5.41 + postage
http://www.amazon.co.uk/The-Waterford-Limerick-Western-Railway/dp/0711031479/ref=pd_sim_14_4?ie=UTF8&refRID=0RY616C7F6VZ5ADXZGBH
Railway Track Diagrams,6 Ireland: 6 €11.38 including postage
http://www.bookdepository.com/Railway-Track-Diagrams-6-Ireland-6-John-Yonge/9781898319689
The Dublin and South Eastern Railway, Ernest Shepherd & Gerry Beesley £ 8.95 + Postage
http://www.amazon.co.uk/The-Dublin-South-Eastern-Railway/dp/1857800826/ref=pd_sim_14_2?ie=UTF8&refRID=10HHA5RTDVT7SRMPT5Y4