Colm & the Lazarus Key  is published by Mercier Press. You can buy it online at:

                                      www.mercierpress.ie
                                       www.amazon.co.uk
                                          www.play.com
                                  www.barnesandnoble.com
    www.amazon.com
                                    www.waterstones.com

It can also be bought in Eason, Waterstones, Dubray and lots of other good bookshops.