I have used the following, free software with success:
GermanAssistant (formerly known as Umlaut Assistant) is a tiny applet to help you in entering into your document the special German characters on non-German keyboards or keyboard support. Hence, an improperly spelled Mueller with a mouse-click becomes M�ller, Schroeder becomes Schr�der and strasse becomes stra�e.
It is available at Yahoo | Mail, Wetter, Suche, Nachrichten, Finanzen, Sport & mehr
Myra
Seattle