Update - http://www.ucc.ie/celt/ has a proofread copy

Update - Found on Google Books

Beatha Aodha Ruaidh Ui Domhnaill PDF PDF (backup)

Starting a Gutenberg Etext for "The Life of Hugh Roe O'Donnell"

Still trying to get the scanner to work properly, but then I will scan in at 600 DPI the I believe out of copyright book "The Life of Hugh Roe O'Donnell".

Here are the first 20 or so pages.