> one with Steven Boyd about the Oscars; "The Oscar"
 
> where George Peppard plays a pseudo-Howard Hughes type."The Carpetbaggers"
 
How about some silents and early talkies?
  Keaton's "Sherlock Jr." (as well as "The Camerman")
  King Vidor's "Show People" (1924)
  Cukor's "What Price Hollywood" (1932)
  Hollywood Cavalcade (1929)
 
There is also a wonderfully cheesy 1976 thing called "Hollywood Boulevard"
directed by Joe Dante and Allan Arkush, a combination debut/parody for Roger
Corman.
                                        msb