help needed contact Librairie de France- sponsor (Abidjan)

Hi dear Internations friends. I'm organising a party with Sunglory children and parents coming soon and would like to have as a sponsor Librairie de France, do you think you can help me by telling me how to ask for a sponsor? who do I need to contact? should I just write a letter asking about it?
I will need english books to give to children on that very day.