Attendees at a service for DJ AM say hundreds of friends gathered at the unique memorial fashioned after a 12-step meeting.
Several guests said attendees participated in the open 12-step process used by recovering addicts in programs such as Alcoholics Anonymous. They requested anonymity because of the nature of the meeting.
Celebrities seen coming and going from the service at the Hollywood Palladium included Lindsay Lohan, Robert Downey Jr., John Mayer and others.
DJ AM, whose real name is Adam Goldstein, was found dead last week in New York. Police officials say pills that appeared to be the powerful painkiller OxyContin were found in his stomach and throat.
Goldstein was a recovering addict working on a reality show to help fellow addicts. He survived a plane crash in South Carolina last year.