Strebel, 35, was last seen on August 18 in the 1700 block of North Orange Grove Avenue in West Hollywood, reported People Magazine.
According to a Los Angeles Police Department official, Strebel went reported missing the same day and could be driving a Toyota Camry.
"This is very unusual for him to be missing. He hasn't done any, not shown up for no reason, no note or anything," his friend Mel Espinoza said.
Strebel is best known for appearing on E!'s "Botched" where he was shown recording his own music.
Strebel said in that episode that his goal was to look like how Bieber used to look when he was "really young."
He said his "ultimate dream" was to duet with the pop star.