She's already a reality TV star and a celebrity fashion designer, but Lauren Conrad is adding another title to her crowded resume: Author!

The Hills star has signed on to write a three-book series of young adult fiction for HarperCollins, People magazine confirmed this morning.

The books – the first of which is due out in Summer 2009 – will be loosely inspired by LC's experience going from ordinary teen to star.

"It's definitely influenced by my own life," Lauren Conrad said.

"The books are about a girl who moves to Los Angeles and stars in a reality show, so obviously there are some similarities."

Some similarities, indeed.

So will any of The Hills co-stars, such as Heidi Montag, Specner Pratt or Brody Jenner, wind up as characters in Conrad's series?

"I'm not trying to do a fictional story based on all my friends in my real life because their stories aren't really mine to tell," says Conrad.

"Some of the characters may symbolize people in my life to a degree, but this is in no way my way of calling anyone out."

Lauren Conrad's best gal pal and Laguna Beach and The Hills co-star, Lauren "Lo" Bosworth, has already been offering advice.

"I run ideas by Lo and I'll ask for her opinion because I value my friends' opinions," says the budding author, who has completed the outline.

But not everyone in Lauren Conrad's life is clued in.

"Honestly I haven't told everyone," she admits. "I've told my best friends and they have all been really supportive. Nobody was worried."