German for Music Lovers by A. Campitelli, University of North Carolina at Greensboro site with loads of helpful resources. Use it often. It is a wonderful site.
German Electronic Textbook by Gary A. Smith, College of William & Mary
Leo Deutsch-Englisch Wörterbuch
Internet Handbook of German Grammar
Deutsch Online by Udo Klinger
German for Travellers
A collection of learning resources from the University of South Florida.
Power-Point presentations are a great way to learn grammar; this site has many, by Liz Caplan-Carbin, USF.
German & Indonesian Teaching Resources by Katherine Munro of West Moreton Anglican College
Deutschkurs, a free on-line German course