If your are looking for a guide in Addis Ababa I highly recommend you Mulugeta (Mulu).
Ethiopia was my first trip alone, and being a girl I was a bit stressed. A friend of mine who already went to Ethiopia, recommended me to contact Mulugeta and I absolutely not regretted it.
Mulugeta literally took care of everything during my stay in Addis. I told him I wanted to have a local experience of the city. He brought me in every cultural places that must be seen in Addis, the touristic ones but also some very typical and local places (most of the time I was the only tourist !). Thanks to him, I had in few days a great insight of the culture and the way of living : drinking bunas (at least twice a day :) ), eating each meal a different type of injera, exploring the dance & music live scene (ethiojazz, azmari ...). As he has a car, I had the chance to explore the countryside of Addis (Debre Zeit, Debre Libanos ...). He also helped me to organize the rest of my trip (Lalibela, Gondar, Mekele, Danakil)
More generally, Mulugeta is very professional and helpful. He speaks well English and has a good knowledge of the city and its country !
If you are looking for an authentic and local experience in Addis, he is your guide ! :)
Here is his contact info :
Mulugeta Derbie Damtie
Email : email@example.com
Tel : +251 912080957