Having trouble finding the perfect gift for everyone on your list? Go shopping with a celebrity! Stars like Lauren Conrad and Ashley Greene have teamed up with the hottest brands and fashion sites on the web to bring you their favorite finds. From a super soft J. Crew fisherman's sweater (Katie Holmes) to an adorable Marc by Marc Jacobs iPhone case (Rachel Bilson) click here to see the best under $100 gift ideas on our favorite celebrity wish lists.