J'ai eu les réponses, je vous recopie les parties intéressantes ici :

Hi Frédéric,
Many thanks for your order. I can certainly look at doing a bulk order for my friends in France
If you can let them know that it can be arranged, all we need to confirm is the amount of books required, I will then be able to calculate a much better shipping rate and I would of course send them by registered mail.
The destination would need to be one single address of course!
A single payment can them be made to my PayPal address and I will ship them to France early in February.

Il me propose de rembourser mon exemplaire pour que je me joigne à la commande groupée.
Je veux bien prépayer/redispatcher si besoin (à la limite à la RGC qui ne devrait pas être trop longtemps après la réception des livres prévue courant février).

Et sur la traduction :

With respect to a French language translation, if somebody wants to take that on, I would certainly help publish the book for them. Hope that helps, don't hesitate to contact me for anything else.

Qui s'y colle ?