Jessica Biel and Justin Timberlake's Wedding Plans: All the Details!

The clock is ticking!

With only four months left till their August wedding, Jessica Biel, 30, and Justin Timberlake, 31, are still hunting for the perfect location.

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Their musts? It needs to be in California and offer plenty of room! "It will be a big wedding," a source tells Us Weekly. "They have lots of people they want to invite."

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Good thing the bride-to-be, 30, has enlisted help from future mother-in-law, Lynn Harless. "She's helping Jessica with every little thing," a source says.

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As for the gown, the actress has already narrowed down her options. "Monique Lhuillier has sent over some sketches," says a Biel pal. "She's Jessica's first choice."

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Credit: London Entertainment/Splash

Though Timberlake, 31, popped the question over the holidays in Jackson, Wyoming, Biel didn't debut her 6-carat engagement ring in public until two weeks ago while exiting The Tavern in L.A. (Though she sho! wed it o ff to Kristen Wiig and Amy Poehler at a Saturday Night Live cast party February 18, she was careful not to be photographed wearing her rock.)