There is indeed a traditional prayer and procedure to be followed when seeking G‑d's assistance in retrieving a lost object.
The following is recited:
Rabbi Binyamin said: All are presumed blind until the Holy One, blessed be He, enlightens their eyes. We know this from the verse:1 "G‑d opened her eyes and she went and filled up the water skin."2
(Say three times:) G‑d of Meir answer me!3
In the merit of the charity which I am donating for the sake of the soul of Rabbi Meir the Miracle Worker may I find (---) which I have lost.
Money is then donated to support the poor in Israel.
Did I forget to mention that you also have to get up and look for the object? :)
Yours truly,
Rabbi Menachem Posner