 A three @-@ volume novel series was written by screenwriter Yoji Enokido and published by Kadokawa Shoten . The novels were released in Japan on June 2000 , October 2000 , and March 2001 respectively . The English @-@ language versions were published by Tokyopop and were released in North America on March 11 , 2008 ; September 9 , 2008 ; and March 10 , 2009 respectively . 
