Ethiopia is not among the top destinations for European or North American travellers, which probably accounts for why it's so difficult to get hold of a decent road map of the country -- or indeed any map at all. The Cartographia map available from Amazon covers covers Eritrea, Djibouti, Somaliland, and Somalia in addition to Ethiopia, a vast area of almost 500 million acres. That's almost three times the size of Texas and almost eight times larger than the U.K. The resulting small scale of the map makes using it for journeys within Ethiopia very challenging. Three inches on the map can represent an entire day's drive along Ethiopia's dusty, rocky unpaved roads, and the names of many smaller towns and villages do not appear at all on the map. (To be fair, they don't appear on roadside signs either!)
That said, the Cartographia map seems to be the only game in town. Maps of Ethiopia by itself are not currently available on Amazon or indeed in the normally dependable London shops Foyles (Charing Cross Rd.) and Stanfords (Long Acre). Nor can you purchase one at the Addis Ababa airport. The Cartographia inset map of Addis Ababa is quite useful for visitors to the capital city, but the accompanying inset map of "The Local Fauna" gives a completely wrong impression of the ubiquity of wildlife in Ethiopia, which is unfortunately very thinly distributed and especially disappointing to travellers who have safaried in Kenya and Ethiopia. While not really heavy duty, the paper on my map held up very well to tears and cuts during a two-week visit to Ethiopia in late 2010.