The 2004 Book of Common Prayer from the Church of Ireland's website; in English and Irish Gaelic

The Church of Ireland website also has a number of additional worshiup resources.

The 1926 Book of Common Prayer

The 1926 Book of Common Prayer in Irish Gaelic

The 1878 Book of Common Prayer, adopted upon disestablishment, as PDF graphics from Google Books.  

(Proposed) Amendments to the Book of Common Prayer (1861): Proposals to move the Prayer Book in a decidedly Protestant direction. 

The 1666 Book of Common Prayer (The English 1662 BCP with variations)

Google Books has an 1849 edition of the original MS copy of this book, richly annotated by Archibald John Stephens, in three volumes: Vol. I, Vol. II, Vol. III (Griffiths 1849/24).
Also from Google Books are 1700 (Griffiths 1700/5), 1739 (Griffiths 1739/10), 1752 (Griffiths 1752/14) and 1785 printings (Griffiths 1785/6), all published in Dublin. The 1700 printing includes "A Form for Receiving Lapsed Protestants" and forms for the Dedication, Restoration and Expiation of churches, along with additional material generally absent in other printings.
The Internet Archive has a 1721 printing by G Grierson of Dublin (Griffiths 1721/4).
("Griffiths" indicates references in David Grifftihs' Bibliography of the Book of Common Prayer.)   

The 1666 Irish Book of Common Prayer was also printed a number of times in Irish Gaelic. Those online include:
1712, (Griffiths 64:3), also from the Internet Archive; 1825 (Griffiths 64:5); 1832 (Griffiths 64:6) and 1861 (Griffiths 64:8)   

Links to several liturgies (A Service of the Word, Compline) may be found on Oremus