There are at least four artists sharing this name: 1) Madu Messenger is UK based dub & reggae male vocalist. He is well known for his cooperation with Steve VIBRONICS on the Scoops label.
http://www.myspace.com/madumessenger 2) Madu (Madina Altynbayeva) is female pop singer from Kazakhstan. 3) Madu is Female pop singer from Indonesia. 4) Madu/Madu765 a Brazilian funky-jazz instrumental project.

Read more about Madu on Last.fm.