Documents for Marriage in France

Surely some of you, British or American, have gotten married here to a French citizen.  Perhaps you could explain to me what on earth is a "Certificate de Coutume"  (sur les lois regissant les mariages dans les etat americains).    It is something  different, apparently from the Certificate de celibate, which testifies that I may legally marry without constraints.  And finally, an "Apostille" delivered by my state of birth.  This is not my birth certificate.    I speak fluent French and asked the officer at the Marie to explain these things, but he said "Ecoutez Madame,"   It is all explained here, as he underlined various paragraphs, "J'ai une marriage qui m'attend!" .     Can anyone enlighten me?    Thanks, Beebe