In which film is Johnny Cash a character?

In which film is Regina George a character? Who played Elle Woods in 'Legally Blonde'? In which film is June Carter a character? Who played Johnny Cash in 'Walk the Line'? Who played Miranda Priestly in 'The Devil Wears Prada'? Who played Andy Sachs in 'The Devil Wears Prada'? In which film is Andy Sachs a character? In which film is Cher Horowitz a character?