Entertainment Tonight.

Want to win iPods autographed by your favorite stars -- including Mariah Carey and Gwen Stefani -- and loaded with their personal playlists? Here's how!

Tonic, a media and e-commerce site focused on activism, is auctioning off between one to five celeb-autographed iPods a week through August on eBay. Each iPod comes pre-loaded with a playlist of 10-20 of the star's favorite songs. The auction is in full swing now with items available from Mariah, Gwen, Pete Wentz and Faith Hill.

Over 70 celebrities will participate in the auction series including U2's The Edge, former President Bill Clinton, Madonna, Beyonce, Cher, Donna Karan, Warren Buffett, Christy Turlington, Britney Spears, Michael Stipe, Gwen Stefani, Mariah Carey, Stevie Nicks, Michael Buble, Ben Affleck, Ellen DeGeneres, Estelle, Faith Hill, Carrie Underwood, Scarlett Johansson, Pete Wentz, Randy Jackson, will.i.am, Kevin Bacon, Gisele Bundchen, Marc Jacobs, Ed Burns, Samantha Ronson, Nick Lachey, Petra Nemcova, Mandy Moore and many others.

Tonic says that 100 percent of the revenue from the auctions will benifit Music Rising, a campaign launched in 2005 to replace musical instruments lost or destroyed by hurricanes in the Gulf Region.