Capoeirista.com: Berimbau - Photograph, description, and audio samples of the capoeira rhythms. [English/Portuguese] - http://www.capoeirista.com/music_berimbau.html
Berimbau - Article by Richard P. Graham and N. Scott Robinson covering history, popular and traditional Brazilian use, and recent developments. - http://www.nscottrobinson.com/berimbau.php
The Art of Building the Berimbau - Covers traditional and modern materials and methods. - http://www.capoeira-shop.com/article_berimbau.html