Headman (Robi Insinna aka Manhead, electro)
There are three artists on Musicbrainz called Headman. This page is for the electro producer/remixer Robi Insinna (sometimes working with Ralph Peter) who released tracks titled "It Rough", "Moisture" and "On" (on Gomma Records), and has remixed material by Franz Ferdinand, Annie, Mylo, The Gossip, and Seelenluft, as well as performing under the pseudonym Manhead.
The rave/trance band consisting of Bent Recknagel and Ralph P. Ruppert can be found HERE.
A drum n' bass artist with the same pseudonym also has one release on MBz.