DJ's from all across the world will be headed to Atlantic City for the 2009 DJ Expo at the Trump Taj Mahal Hotel & Casino. The weekend is billed as the "world's largest gathering of professional DJ's."   The event will feature 130 vendor booths, 25 education seminars, 50,000 square feet of exhibitor space and night parties at some of Atlantic City's top venues.   The weekend will kick off on August 10 at Club Worship inside of The House of Blues Atlantic City and will feature DJ's Chris Wills, Rod Carrillo, Camel Rider, Peter Presta, Ray Roc and Lost Daze.   On August 11, the Promo Only party will also be held at The House of Blues and will be hosted by Three6Mafia, Lilian Garcia, Brooke Hogan and Joanna Krupa. The party will feature performers from all areas of dance music and dance radio.