Business Visa and Work Permit (Addis Ababa)

Hello everyone,
I'll be moving to Ethiopia in several months for a new job and I'll need to arrange a business visa and work permit. I've searched a bit online to find all the necessary requirements, but I've not found anything too clear and I'm afraid some of the info is outdated. If any of you out there could tell the the basics of what I should do, or point me in the right direction to find this info myself, it would be GREATLY appreciated. I'll buy you a drink when I land in Addis :)

Thank you in advance,
Thomas