You can order The Revelations of Arran Nak at your local bookstore or buy it online. The list price is $16.95. Here are some links to online bookstores in the US (links will open in a new window):  
 

Publisher's Web Site    In Association with Amazon.com    Barnes and Noble.com    Booksamillion.com
 
 
Here are a few links to online stores in Europe, Canada, and Asia (links will open in a new window):

Great Brittain www.amazon.co.uk.  
Germany www.amazon.de/.  
The Netherlands www.bol.com/. (currently unavailable. Dutch customers go to www.amazon.de--free shipping to the Netherlands)  
France www.amazon.fr/.  
Canada www.amazon.ca/.  
China www.amazon.cn/.  
Japan www.amazon.co.jp/.