The culture of self-released music and sound art is one of the most vital, yet most overlooked, phenomena resulting from the 20th century revolution in communications technology. In this volume, Thomas Bailey surveys a fascinating realm of creative activity and identifies the key individuals and developments responsible for its continued relevance in the present age. From the networked "mail art" of the 1970s, to the home-taping boom, to the establishment of music labels dealing solely in digital sound files, this culture provides valuable insight into the evolution of the "official" art market and the artists who bypass it. Along the way, we are introduced to a world where networks are artworks in themselves, where blank tapes and recordable CDs are fashioned into elaborate art objects, and where relative freedom from creative supervision leads to both colorful innovations and violent aesthetic extremes. 'Unofficial Release' features material on mail art, cassette culture, industrial music, handmade packaging, releasing addiction, anti-promotion, net-labels, digital file sharing, circumventing censorship, extremist metal, sound poetry, imaginary music, 'outsider' art, tape nostalgia...and much more!