Blake Shelton's all-star lineup for Wednesday night's 'Healing in the Heartland' benefit concert now has even more A-list names attached to it. In addition to previously announced stars Reba McEntire and Miranda Lambert, three country acts, a hip-hop superstar and a rocker will play during the live NBC telethon.

Luke Bryan, Rascal Flatts, Darius Rucker and One Republic's Ryan Tedder are new to the bill, as is Shelton's fellow 'The Voice' judge, Usher. The show will originate from the Chesapeake Energy Arena in Oklahoma City. Viewers will be able to donate live as they watch, with all money going to the United Way of Central Oklahoma May Tornadoes Relief Fund.

Tickets for the show sold out in in 30 seconds on Saturday, but fans can watch it on NBC beginning at 9PM ET. "Everyone has their way to help, and mine as an entertainer is to perform to help raise money and awareness for this tragedy," Shelton said when announcing the show last week. "This is why I want to do this special and especially hold it in Oklahoma City, which is near ground zero."

Vince Gill is also going to perform during the May 29 telecast. He's a native Oklahoman, as are McEntire, Shelton, Rascal Flatts' Joe Don Rooney and Tedder. Style, G4, Bravo, E! and CMT will also broadcasting the event, which was organized after the May 20 EF5 tornado that hit Moore, Okla.