Backstage at Oprah Winfrey's 'Surprise Spectacular' Show

Last night marked the end of era as talk show legend Oprah Winfrey taped one of her final farewell episodes in Chicago, and ET's Nancy O'Dell was there in the middle of all the action.

An estimated 13,000 fans packed the venue to celebrate Winfrey in what turned out to be a star-studded extravaganza. Celebrities in attendance included: Maria Shriver, Tom Hanks, Tom Cruise, Beyonce, Halle Berry, Rascal Flatts, Stevie Wonder, Will Smith, Jada Pinkett-Smith, Simon Cowell, and the list goes on.

"This is a fantastic night," beamed Jamie Foxx as he met with Nancy moments after taping. With so many famous faces, Jamie confessed that being backstage felt like he was in "the Jurassic Park of Celebrities."

Madonna praised Oprah as her "only living role model," calling her the only woman she could think of that a woman could "look up to" and "model herself after."

Best friend Gayle King commended the event's producers who, with only a few hours, set up the larger-than-life undertaking and managed to put on a "well done" show.

Watch the video to catch more backstage interviews, and check out ET's Facebook page for Nancy's exclusive photos.

"The Oprah Winfrey Show" will air its final episode May 25, 2011.