Although you specifically ask for novels, I would also recommend that you take a look at a few actor/actress biographies if you want a "real" look at what goes on behind the scenes in the film industry. Some of the stuff is really shocking and eye-opening. If you purely want something fictional about the glitz and glamour of Hollywood, then you shouldn't have any trouble tracking interesting stuff as it is practically a genre on its own. My favorites are;

American Dream Machine (2014). This novel is by Matthew Specktor, who is not only a novelist but also a screenwriter, so he knows a thing or two about Hollywood. Hid dad is also a talent agent for the top agency in film, Creative Artists Agency. With clients like Sandra Bullock, George Clooney, Daniel Craig, Tom Cruise, Robert De Niro, Johnny Depp, and Robert Downey Jr., this agency is pretty unbeatable in the business. In this book, Matthew writes about two talent agents who start from nothing and go on to practically shape the industry before going to war with each other.

Get Shorty (1990). This novel is by Elmore Leonard, although most people only know the 1995 movie or the recent television series based on it. If you've watched either of those, there's not much more to say about Get Shorty apart from the fact that it is hilarious. If you have not watched the film or series, then you'll still love the book.

Read Laughing Gas by P.G. Wodehouse, it's extremely funny. It's very old, but it does feature the golden age of the film industry. One of the characters, Reggie, is an English Earl who is sent to Hollywood to find his cousin and bring him home before he does anything stupid, like marrying an American gold-digger. This goes pear-shaped when Reggie has to go to the dentist because of severe toothache, only to wake up as a 12-year old movie star called Joey Cooley. The two somehow switched bodies when given anesthetic. Reggie finds that the life of a Hollywood brat is not all that it is cracked up to be, while Joey uses his new grown-up body to get back at everyone who wronged him.

My personal taste runs more towards horror, so these books might not be what you are looking for, but they do use Hollywood or the film industry as a backdrop.

Clive Barker - Coldheart Canyon ~ This one is about a movie star who thinks that plastic surgery is the answer to getting himself back in the limelight. As is often the case, the operation is botched, and the actor ends up with a disfigured face. To stay out of the public eye while recovering, the actor moves to a secluded area just outside of Hollywood called Coldheart Canyon. This novel is by horror maestro Clive Barker, and its description as a Hollywood ghost story is very apt.