Amy Winehouse's Billboard U.S. Chart History
Singer Amy Winehouse performs onstage at Lollapalooza in Grant Park on August 5, 2007 in Chicago, Illinois.

Mark Ronson, the producer behind Winehouse's breakthrough album "Back to Black," deeply mourned the loss on Twitter, as did so many others. "She was my musical soulmate and like a sister to me," he wrote. "This is one of the saddest days of my life." Read more musician tweets about Winehouse's passing.

Adele, clearly influenced by Winehouse' blue-eyed soul revival, wrote about the singer's passing on her official site. "Amy paved the way for artists like me and made people excited about British music again whilst being fearlessly hilarious and blase about the whole thing," Adele said. "I don't think she ever realized just how brilliant she was and how important she is, but that just makes her even more charming. Although I'm incredibly sad about Amy passing, I'm also reminded of how immensely proud of her I am as well. And grateful to be inspired by her. Amy flies in paradise."

Dead At 27: Nine Artists Gone Too Soon

Courtney Love chimed in with her devastation over the loss of her friend. "I'm not even going to say, 'Waste of glorious sublime talent,' which I feel," Love told Rolling Stone Saturday. "I'm fucking gutted. I tried with her, I tried twice."

"When you love someone who suffers from the disease of addiction you await the phone call," begins Russell Brand's letter about addiction and his longtime friend Amy Winehouse. "There will be a phone call. The sincere hope is that the call will be from the addict themselves, telling you they've had enough, that they're ready to stop, ready to try something new. Of course though, you fear the other call, the sad nocturnal chime from a friend or relative telling you it's too late, she's gone." Read the full letter, which appeared on his official site.

Kelly Clarkson issued a statement via WhoSay, in which she mourns the loss of her acquaintance Winehouse and discusses pitfalls of fame. "I'm angry," she wrote. "What a waste of a gifted person. What a shame she saw no hope and continued living her life in that manor. I have been that low emotionally and mentally and that is overwhelming. I keep asking myself why some of us are spared and the others are made examples. I'm very angry and sad. I don't know why it's bothering me so much. Sometimes I think this job will be the death of us all, or at least the emotional death of us all."

As an admirer, Lady Gaga wrote of Amy's influence via Twitter: "Amy changed pop music forever, I remember knowing there was hope, and feeling not alone because of her. She lived jazz, she lived the blues." Read more musician tweets about Winehouse's passing.

(Additional reporting by Erica Thompson)

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