Last Night at Chateau Marmont by Lauren Weisberger - is my latest read. While I really enjoyed the book (as I have enjoyed all of Lauren Weisberger's novels), I'm not sure I would have wrote the ending the way it is... without spoiling it for you, I would have preferred it to end differently.
By the way, check out the actual website for the real Chateau Marmont! It's peppered with photos of "old Hollywood" stars.
You must check out the Chateau on Wikipedia. Read the notable people and events section for some entertaining facts.