Michael Lohan knows how hard it is to make it in the big city -- he can't even get into rehab.
We're told Michael headed for the desert last Thursday ... to Rancho Mirage, home of the Betty Ford Center and temporary digs of Lindsay Lohan.
Michael was turned away by security. He was told visiting hours were over. Michael tells us he asked if he was on a "no contact" list and they told him no. But we're guessing his name is right under Osama's.
Michael says he's been on the horn with people at Betty Ford, asking them to please involve him in family therapy with Lindsay.