According to the information here, the release dates for all things Ringish are:
The Lord of the Rings: The Two Towers
~Theatrical Cut DVD/Video: Late August 2003
~Extended Cut DVD/Video: November 2003
The Lord of the Rings: Return of the King
~Theatrical Release: Dec. 17, 2003
~Theatrical Cut DVD/Video: August 2004
~Extended Cut DVD/Video: November 2004