Amazon.com has Avatar: The Last Airbender The Complete Series Pre-Order (16-Disc DVD) on sale for $29.99. Shipping is free with Prime or if you spend $35 or more.

Alternatively, Rakuten.com has Avatar: The Last Airbender The Complete Series Pre-Order (16-Disc DVD) on sale for $27.64 + $2.90 shipping = $30.54.

Note, product is scheduled to be released on October 6, 2015