From the description on Goodreads of Audrey, Wait! by Robin Benway
California high school student Audrey Cuttler dumps self-involved Evan, the lead singer of a little band called The Do-Gooders. Evan writes, “Audrey, Wait!,” a break-up song that's so good it rockets up the billboard charts. And Audrey is suddenly famous!What did you find???
Now rabid fans are invading her school. People is running articles about her arm-warmers. The lead singer of the Lolitas wants her as his muse. (And the Internet is documenting her every move!) Audrey can't hang out with her best friend or get with her new crush without being mobbed by fans and paparazzi.Take a wild ride with Audrey as she makes headlines, has outrageous amounts of fun, confronts her ex on MTV, and gets the chance to show the world who she really is.
(I bought this from a store called Fully Booked)