Hi Edmund,

a fine book is:
Räuber- und Landsknechtslieder : Texte und Noten mit Begleit-Akkorden / hrsg., übers. und erl. von Walter Scherf
   Frankfurt am Main : Fischer-Taschenbuch-Verl., 1981
(Fischer-Taschenbücher ; 2963)
ISBN 3-596-22963-4

This collection contains German, Slawic and English songs about famous robbers and historical songs of lansquenets (soldiers of fortune, about 1500 till the end of the 30-years war), with tunes.
It is out of print, but it can be bought at the German branch of Amazon, used, from € 2,50 on. Here you'll find the songs referred to by our German mudcatters

Sing and enjoy
Wilfried