Hello sir/madam,
You can contact to the Passport authority use
RTI Act, 2005 in asking the passport No. by giving your husband's name (Full Name), father's Name and mother's name.
If you have local address you can mention if you are sure that he might have mentioned the same address in passport application.
I can advise you that you can contact very close relative of your in-laws and husband.
hope you got some idea.
rakatkam.