Hi Katyiona
Don't know whether you found what you have been looking for, but in the interim try the the Lonely Planet Guide: Africa (12th Edition ISBN 978-1-7-74104-988-6 USD36.99) as this guide have tons of lots of information that is factual, up to date and relevant.
Also, highly recommended is Bradt Guides (bradtguides.com/Book/568/Ethiopia.html) which is an exhaustive resource of very factual and current information on Ethiopia (probably the best there is). I see the Ethiopia Guide (6th Edition) is only due in September 2012 (ISBN: 9781841624143) but ISBN: 9781841622842 is available and is a comprehensive resource.
Hope this helps.