Is there any moderator who can help?
We, as staff members, do nothing about stuff like this. We do not moderate scams, which is explicitly stated in the
forum rules (19. Possible (or real) scams and Trust ratings are not moderated (to prevent moderation abuse)). We are not here to babysit, how harsh that might sound. If the guy ripped you off, all you can do is a create a scam accusations (like you did), post evidence that you were indeed scammed and hope that the guy is given enough negative trust ratings to never sell anything ever again.
Anyway, the e-book sounds very fishy and he now has a scam accusations against him, so I've tagged them.