If Philippa above (or anyone else) is still looking for verses to "Pòsadh Piuthar Iain Bhàin", you can find some of them here at:

http://www.bbc.co.uk/alba/oran/orain/posadh_piuthar_iain_bhain/

If anyone happens to need the rest of the words, just send an e-mail to me at alltandubh@gmail.com and I'll try to rouse myself to type them out for you.