LightSource.com does not sell products - only our ministry partners do.  You will need to contact the ministry directly regarding product orders they offer and if they sell a DVD of a particular episode or series you like.
 
You can find a complete listing of the ministries on LightSource.com here: http://www.lightsource.com/ministries/. On their program's page there is Contact Information in the left hand column, or you may click on the "Contact Ministry" Tab above the player screen to email.