Celeb Sightings! See Where Your Favorite Stars Hung Out This Week

Credit: Mike Coppola/ Getty

--Whitney Port stepping out for the 3rd Annual BeautyCon Summit presented by ELLE Magazine at Pier 36 in NYC.

--Nicolas Cage announcing Axl Rose and Guns N' Roses — who were guzzling Beau Joie champagne and Casamigos tequila! — at Beacher's Madhouse at the MGM Grand in Las Vegas.

--Bethenny Frankel and boyfriend Mac Cerussi - nicknamed Macbeth! - having dinner at Harlow restaurant in Sag Harbor, NY.

--Lena Dunham ordering a carrot, beet and ginger smoothie at The Bedford in Brooklyn.

--Karina Smirnoff sipping TY KU cocktails at the Dancing With the Stars Wrap Party in L.A.

--Rosario Dawson supporting Hollywood Domino at their Dancing Spies Ball benefitting PCI Media Impact in Cannes, France.

--Macklemore dining on a pretzel panini and truffle fries with a friend at David Burke at Bloomingdale's in NYC.

--Ethan Hawke and wife Ryan Hawke hosting a book release party for Anna Godbersen's The Blonde at their home in NYC.

--Lady Gaga getting up close and personal with fans who won the Absolut Gaga contest at her ArtRave tour stop in Edmonton, Canada.

--Austin Mahone performing songs off his new EP, The Secret, at the launch of the Billboard Twitter Real-Time Charts in NYC.

--Mark Ballas celebrating his birthday with pals Cheryl Burke, Nikki Reed and Derek Hough over dinner at Katsuya in Hollywood.

--Ryan Seacrest hanging in the DJ booth at the new Drai's Nightclub with Victor Drai and DJ Eric Prydz inside The Cromwell, the first stand-alone boutique hotel on the Las Vegas strip.

--Arnold Schwarzenegger and Maria Shriver turning up for the friends and family opening event of son Patrick Schwarzenegger's new restaurant Blaze Pizza in the Original Farmer's Market in L.A.

--Katie Holmes picking up frozen yogurt with daughter Suri at 16 Handles - who just launched the special edition flavor Caramel Popcorn Finale for the Tony Awards - in NYC.

--A newly single Nick Loeb spending Memorial Day Weekend with a guy friend at Don Julio’s StadiumRed Estate BBQ in Sag Harbor, NY.