Indeed. Only the content creator can send you the .CDPs if they wish to, unless (as in the case of the Landrvr1 content) permission has been given previously to distribute the content via email or similar.
If this is not the case, as a user found out on my forum recently, it's against copyright law for another user (who is not the creator or someone authorised to distribute said content) to distribute the file(s) in any form.
Shane