These are all really good yound adult books my Meg Cabot:
Pants On Fire by Meg Cabot. It's about a girl who basically has everything (popular best friend, good grades... and TWO boyfriends.) It's really funny because then her friend from eighth grade come back to town (everyone hates him) and she falls head over heals for him too.
All-American Girl and All-American Girl Ready Or Not by Meg Cabot. It's about an outcast girl who happens to save the presidents life. Suddenly everyone at school wants to be her friend, but she doesn't really care... What she does care about is the presidents son...
How To Be Popular by Meg Cabot. It's about a girl who comes across an old book in her grandma'a attic called how to be popular. So, she follows the rules of the book hoping to become popular.
Jinx by Meg Cabot. If you liked Twilight, then you'll like this book. It's about a girl who has bad luck all the time so she moves in with her aunt and uncle. He sister is into witchcraft and I don't want to spoil the rest, but it fairly good.
Teen Idol by Meg Cabot. This is about a girl who has an advice column in her school newspaper. So, when a famous actor comes to her school and she's the only one who knows about it, chaos occurs!
The Mediator series by Meg Cabot. I've only read the first two, but they are VERY good. It's about a girl named Suze who moves to California from New York because her mother just remarried. Oh, and Suze can see ghosts...