Zac Efron suited up to film scenes at the Iowa Speedway on Friday. - Jeff Steinberg/PacificCoastNews.comLadies and gentleman, start your engines!

Zac Efron, 23, set hearts racing Friday when he donned a uniform to shoot scenes for his upcoming movie "Heartland" at the Iowa Speedway in Newton, Iowa. The flick stars Zac as a rural Iowan teen named Dean Whipple, who has dreams of becoming a professional race car driver, which doesn't sit too well with his farming father played by Dennis Quaid.

Interestingly enough, there was an actual race -- the Prairie Meadows 200 ARCA Series -- taking place on the day of filming. According to Iowa Speedway president Jerry Jauron, "Efron's character catches a big break to race, and it just so happens that he races in the ARCA races at the Iowa Speedway. The goal is for Zac to look as if he's been racing his whole life."

Of course, Zac didn't actually get behind the wheel and compete, but footage from the race -- including infield shots and the fans in the grandstand -- will appear in the actual flick.

The rest of the film is primarily being shot in

Demi Lovato is attempting a comeback with "Skyscraper." - SPW/Splash NewsAfter her rehab stint last year for "emotional and physical issues" that included eating disorders and cutting, I thought that former Disney star Demi Lovato would fade away -- especially after the 18-year-old announced she was leaving her show "Sonny With a Chance." Instead, Demi has spoken publicly about her struggles and reinvented herself with her comeback song, "Skyscraper."

The inspiring ballad, which seems to say Demi can rise above her problems, was released Tuesday, and quickly jumped to No. 1 on iTunes. The video for the track came out a day later, and features Demi staring into the camera and crying in a clip that's much more raw than any of the slick, upbeat videos she's put out in the past.

Demi's fans and friends in Hollywood from Katy Perry to Kim Kardashian have shown their support on Twitter. Even former BFF Selena Gomez wrote, "SO, SO proud of @ddlovato #skyscraper Incredible, beautiful and so inspiring."

While the song sounds like it was written specifically for her

"Harry Potter" trio Daniel Radcliffe, Emma Watson, and Rupert Grint took what might be their final walk down the red carpet together on Monday at New York's Lincoln Center. The three -- along with hundreds of fans -- celebrated the premiere of "Harry Potter and the Deathly Hallows -- Part II," which hits theaters Friday.

"It's been the most amazing roller coaster ride," said Watson, who donned a dress from Bottega Veneta's Fall 2011 collection, platform peep-toe shoes by Giuseppe Zanotti, and jewels by Lorraine Schwartz for the occasion. Just in case her emotions got to be too much, Emma, 21, also wore waterproof mascara, which she didn't need, according to People.

Check out what Watson had to say:

Emma's leading man, Daniel Radcliffe, suited up and raved about the scene where his character, Harry, meets his mentor, Dumbeldore, for the last time. "There's something very poignant and unusual about it," Radcliffe, 21, told USA Today. He added that he felt it was "bizarre" to be

Ever wonder what "Gossip Girl's" Leighton Meester is really like? Find out in Just Jared's new interview with the 25-year-old starlet, where she steps into Lacoste's Manhattan showroom alone and answers questions about everything from her hair color (she may be a natural blonde, but does she feel like she's more of a brunette?) to the reason she named her dog Trudy (funny story). The multi-talented Leighton even whips out a guitar and performs one of her own beautiful ballads. Check it out!

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Teen queen Selena Gomez is having a moment. Not only does she have a new album, When the Sun Goes Down, and a new movie, "Monte Carlo," but she also just bumped her boyfriend Justin Bieber from the top spot on Billboard's Social 50 chart. The chart, which considers the artists most active on social networks by counting weekly pageviews plus fans/followers/friends, has only been ruled by four other acts: Lady Gaga, Rihanna, the Black Eyed Peas, and the Biebs. Not bad company!

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The 18-year-old star celebrated with a shopping spree on Wednesday in London, where she's been promoting her new tunes. Selena wore a sparkly top with cap sleeves, skinny jeans, and gray booties as she popped in at stores such as All Saints. Even there, though, the "Wizards of Waverly Place" actress ran into a few fans, for which she kindly signed autographs and posed for pics.

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Let the fist-pumping begin! "Jersey Shore" star Paul "DJ Pauly D" DelVecchio turned 31 on Tuesday, and he wasn't about to let his special day pass without a celebration. The tattooed tanzilla and his family -- visiting all the way from Rhode Island -- marked the occasion by riding the roller coaster and more on the boardwalk in Seaside Heights, New Jersey. Pauly D was even spotted carrying a "Happy Birthday" card from a fan.

But the perfectly-coiffed Pauly wasn't the only "Jersey Shore" castmember to blow out candles recently: Mike "The Situation" Sorrentinoturned 30 on July 4. The Situation partied down by the shore with therest of the cast -- just like they do every weekend!

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The entire gang was supposed to be back by the ocean to film Season 5 of their reality hit after wrapping up Season 4 in Italy last month, but rumor has it that one of them -- Vinny Guadagnino -- left the house for good last week. An MTV rep told US Weekly that, "We don't comment on series while they are in

Willow Smith rocks her funky sense of style. - Demis Maryannakis/PacificCoastNews.comTen-year-old Willow Smith came out with a bang with her song "Whip My Hair," but unlike most novelty acts (How cute! She's a kid!) Willow doesn't show any signs of becoming a blip in pop culture. This past spring, the rising star opened for none other than teen heartthrob Justin Bieber on tour. Now, her proud papa, Will Smith, is reportedly in talks with actress and writer Emma Thompson to draft a remake of the movie "Annie," in which she would play the lead. If it's anywhere near as successful as her brother Jaden's remake of "The Karate Kid" -- it took in more than $176 million domestically, according to Box Office Mojo -- watch out world!

Meanwhile, Willow -- who is a budding fashionista -- has been busy enjoying her summer. She and her brother tied to win BET's Young Stars Award last Sunday in L.A., then she flew east, where she's been busy taking Manhattan. The tween was photographed shopping on Thursday and showing off her funky sense of style in a T-shirt emblazoned with the

Taylor Swift goes retro in the August Teen Vogue . - Daniel JacksonEveryone's always so busy trying to figure out singer/songwriter Taylor Swift's tunes and what they say about her love life (Is this one about Joe Jonas? Is that one about John Mayer?), that it's much more rare when interviewers ask her about the normal stuff ... like herself. Taylor talks about what she does in her down time, what other careers she'd be willing to try, and much more in the August issue of Teen Vogue.

First, just like the rest of us, Taylor has her guilty pleasures when it comes to pop culture. The 21-year-old admits to the magazine that hers include MTV's "Teen Mom" and "16 and Pregnant." She also likes "'90s one-hit wonders, watching YouTube videos of kittens, the app CatPaint ... I CatPaint all my pictures. It's weird." But when she needs to be inspired, she usually listens to a soundtrack that includes Tal Bachman's "She's So High," Alanis Morissette's "You Learn," and Augustana's "Shot in the Dark."

Daniel Jackson

Taylor Swift's Fashion Timeline

The pop princess also confesses