Is 'Wedding Crashers' and 'Hot Rod' star ISLA FISHER a shopaholic? She sure is -- in her new Disney big-screen comedy, that is -- and ET is with her on the set of the movie at Barney's New York!

Based on the best-selling series of books by British author SOPHIE KINSELLA and produced by 'Pirates of the Caribbean' king JERRY BRUCKHEIMER, 'Confessions of Shopaholic' casts Isla as Rebecca, a sweet and charming New York City girl who has a serious problem: she's hopelessly addicted to shopping and drowning in a sea of debt.

But things take a positive turn in Rebecca's life when she lands a job as an advice columnist for a new financial magazine -- published by the same company that distributes the top fashion mag she dreams of working for. The column turns Rebecca into an overnight star, but will her growing debt issues derail her career and destroy her love life?

Also starring HUGH DANCY, JOAN CUSACK, KRISTIN SCOTT THOMAS, JOHN LITHGOW and JOHN GOODMAN, and directed by P.J. HOGAN ('My Best Friend's Wedding'), 'Confessions of Shopaholic' is scheduled to hit theaters in 2009.