OUTSIDER MADE AWAY WITH ALL PAPERS!

What is the procedure for trying to locate a will of a deceased person that we believe was written?

The advice I found was:
Go thru the checkbook and see if he wrote a check to an attorney, who may be holding it.
Contact his friends and other family members and ask if any recommended an attorney.
Go thru all the papers he has.

Problem: his housekeeper hid his passing from us and has (had)all of his personal items in her posession. What now?

Get a lawyer and go to court to make her deliver the papers to you. She had no right to steal them, if that is what she did. And file for probate as if he died without a will, assuming there were any assets. (But be prepared -- the housekeeper may claim he gave them to her before he died.)