Gottfried Leibniz resources at the European Graduate School - Resources on the famous German Philosopher and Mathematician Gottfried Wilhelm Leibniz having invented the differential and integral calculus. - http://www.egs.edu/resources/gottfriedleibniz.html
Leibniz: Harmony - Compilation, that describes the uses of logic and harmony. - http://www.philosophypages.com/hy/4j.htm
Gottfried von Leibniz's Step Reckoner - In the 1670s, Gottfried von Leibniz took mechanical calculation a step beyond his predecessors and invented a mechanical Step Reckoner. - http://www.maxmon.com/1670ad.htm
Leibniz - Complete book on Leibniz. Originally published by Oxford University Press. - http://etext.leeds.ac.uk/leibniz/leibniz.htm
Leibniz Society of North America - The Leibniz Society of North America provides "The Leibniz Review" a magazine on Leibniz, as well as a "Leibniz Society Newsletter". - http://philosophy2.ucsd.edu/~rutherford/Leibniz/leibsoc.htm
G.W. Leibniz: Texts and Translations - A clearinghouse for information on English-language translation of this philosopher's works. Includes bibliographies, a biographical timeline, and some online translations. Also hosts the official site of the Leibniz Society of North America. - http://philosophy2.ucsd.edu/~rutherford/Leibniz/
Leibnitiana - Includes biographical information and links. Maintained by Gregory Brown of the University of Houston. [Requires Java] - http://www.hfac.uh.edu/gbrown/philosophers/leibniz/