As I said to an earlier posting it is out of print - I spoke to Mrs Young about 3 weeks ago and she said the information in it would be included in a new edition of Barneys History of Man under the Norse which she intended to bring out later this year.
There may be some second hand copies available (try www.manxbooks.com) or see my web pages
www.ee.surrey.ac.uk/Contrib/manx under organisations/publishers for other bookshops on the Island