I reviewed Audrey and Bill: A Romantic Biography of Audrey Hepburn and William Holden, a crummy book about the two stars' affair during the making of Sabrina in the early 50s, for The Washington Post. If decades-old Hollywood gossip is your bag, I recommend Karina Longworth's podcast You Must Remember This. The author of Audrey and Bill, Edward Z. Epstein, is a former publicist; Longworth is film critic and historian. It's a crucial difference.
UPDATE: Whoops, You Must Remember This already covered Hepburn and Sabrina. I should've checked that. Also, I stumbled upon this 10-year-old Slate piece about Arnold Schwarzenegger's incredibly luxe deal for Terminator 3: Rise of the Machines, by one Edward Jay Epstein. It's richly reported and has a strong point of view, two qualities Audrey and Bill lacks, in my opinion. Having written for Slate myself, I know that their editors encourage this sharper, more argumentative tone, but even allowing for that, this Schwarzenegger piece and Audrey and Bill still don't read like the work of the same author. Probably because they're not: Edward Jay's site is here; Edward Z.'s is here. But that's still a pretty big coincidence.