There have been two major editions of Wagner's writings, in German, as
follows: 

* 'Gesammelte Schriften und Dichtungen', 10 volumes, Leipzig 1871-83. The
  first edition of Collected Writings, prepared under RW's direct super-
  vision. 

* 'Sämtliche Schriften und Dichtungen', 16 volumes, Leipzig 1911-1916.
  Currently it is the most complete edition of Wagner's prose and poetry. 

The nearest thing to a complete edition available in English is 'Richard 
Wagner's Prose Works' in 8 volumes. For details, see the Wagner Books FAQ.

English translations of some of Wagner's shorter prose works, together with
letters and articles by Wagner and his close associates, can be found online
at the 'Wagner Library': < http://users.belgacom.net/wagnerlibrary/ >, an
ongoing project of Patrick Swinkels.

Some parts © 2009 Advameg, Inc.