Tony Iommi: "Yesterday 16th May my dear, dear friend Ronnie James Dio passed away at 7.45am LA time. I've been in total shock I just can't believe he's gone. Ronnie was one of the nicest people you could ever meet, we had some fantastic times together. Ronnie loved what he did, making music and performing on stage. He loved his fans so much. He was a kind man and would put himself out to help others. I can honestly say it's truly been an honor to play at his side for all these years, his music will live on forever. Our thoughts are with Wendy Dio who stood by Ronnie until the end, he loved her very much. The man with the magic voice is a star amongst stars, a true professional. I'll miss you so much my dear friend."

Metallica's Lars Ulrich: "Dear Ronnie, I just got off stage in Zagreb. I was met with the news that you've passed on. I'm kind of in shock, but I wanted you to know that you were one of the main reasons I made it onto that stage to begin with. When I first saw you in Elf, opening for Deep Purple in 1975, I was completely blown away by the power in your voice, your presence on stage, your confidence, and the ease with which you seemed to connect to 6,000 Danish people and one starry-eyed 11 year old, most of whom were not familiar with Elf's music. The following year, I was so psyched when I heard the results of you joining forces with my favourite guitar player . You guys sounded so right for each other and I instantly became Rainbow's #1 fan in Denmark. In the fall of 1976, when you played your first show in Copenhagen, I was literally in the front row and the couple of times we made eye contact you made me feel like the most important person in the world. The news that you guys were staying in town on your day off somehow embedded itself in my brain and I made the pilgrimage to the Plaza Hotel to see if I could somehow grab a picture, an autograph, a moment, anything. A few hours later you came out and were so kind and caring... pictures, autographs and a couple minutes of casual banter. I was on top of the world, inspired and ready for anything. Rainbow came to Copenhagen a couple more times over the next few years and each time you guys blew my mind, and for a good three years were my absolute favourite band on this planet. Over the years I've been fortunate enough to run into you a half dozen times or so and each time you were as kind, caring and gracious as you were in 1976 outside the hotel. When we finally got a chance to play together in Austria in 2007, even though I may not have let on, I was literally transformed back to that little snot nosed kid who you met and inspired 31 years earlier and it was such a f***ing honor and a dream come true to share a stage with you and the rest of the legends in Heaven & Hell. A couple of weeks ago when I heard that you were not going to be able to make it to the Sonisphere shows that we would be sharing this June, I wanted to call you and let you know that I was thinking of you and wish you well, but I kind of pussied out, thinking the last thing you needed in your recovery was feeling obligated to take a phone call from a Danish drummer/fan boy. I wish I'd made that call. We will miss you immensely on the dates, and we will be thinking of you with great admiration and affection during that run. It seemed so right to have you out on tour with the so-called Big Four since you obviously were one of the main reasons that the four bands even exist. Your ears will definitely be burning during those two weeks because all of us will be talking, reminiscing and sharing stories about how knowing you has made our lives that much better. Ronnie, your voice impacted and empowered me, your music inspired and influenced me, and your kindness touched and moved me. Thank you. Much love, Lars."

Glenn Hughes: "It is a very sad day today... I have lost a very dear friend. Ronnie was a true leader of heavy metal ... an icon and a visionary... there will never be another like him. Ronnie gave me wisdom, and showed me great compassion when he was in Elf, all those years ago, when we were on tour together in my time in Deep Purple. He was a beautiful soul, kind, considerate and a wonderful teacher. Someday I'll be bringing your microphone up there with me, and we'll sing a song, and share a Vindaloo together... I'll miss you mate."

Megadeth's David Ellefson: "He was truly one of the 'good guys' in this business and a consummate pro, someone we can all take a que and learn from. We are all fans of his and he did many great things for Megadeth and its members, starting starting as far back as his 'Dream Evil' North American tour in which we were the support band during the 'So Far, So Good...So What' tour. . . I'm very thankful to have gotten to know and tour with him in both Megadeth and with Tim 'Ripper' Owens. Wendy Dio looked after Ripper's European tour where we played several shows with Heaven & Hell and we got to have many good moments with Ronnie during that tour. He is missed by us all. Our prayers go out to him and his family at this time. Other than that, time to rest before the European trek starting end of May in Lisbon, Portugual. See you then!"

Ritchie Blackmore: "Ronnie had a unique and wonderful voice. He will be sadly missed in the rock and roll world."

Former Dio guitarist Rowan Robertson: "I am privileged to have been a part of Ronnie James Dio's life and music. His closest ones are in my thoughts."

Sebastian Bach: "Crying right now in remembrance of my hero and friend Ronnie James Dio. Dio died this morning and he was a major, major part of my life. I got to do shows with him and work with him and I loved Dio my whole life. Thanks so much the world has lost one of the best. Your last album was your best. Of course"

Billy Corgan: "R.I.P. Ronnie James Dio. I only got to meet him once and I can honestly say he was the nicest person I have ever met in music. Ronnie was a true gentleman, and obviously one of the best rock singers there will ever be. What a sad loss today.

Queensryche: "Ronnie James Dio was undoubtedly one of heavy metal's greatest performers and will continue to influence the world of heavy metal forever. He was certainly a very big influence on Queensryche and along the way became a cherished friend too. We will all miss him greatly, but Ronnie will live on every time we raise our metal horns high! The man on the silver mountain will always be our rainbow in the dark."

Geezer Butler posted a picture of Dio on his website, with the caption: "Goodbye My Dear Friend."

Twisted Sister: "The members of Twisted Sister along with millions of metal fans around the world mourn the death of our friend Ronnie James Dio. Ronnie not only was a giant in the world wide metal scene, but he was also one of the nicest people you would ever want to meet. Beginning in 1983 when we first toured with Ronnie in Canada, and continuing over the last 7 years when we played dozens of festivals around the world, Ronnie was one of the most supportive and gracious members of the music community. Our thoughts and prayers are with Wendy and Ronnie's family."

Slash: "Ronnie died at 7:45 a.m. this morning, but his music will live for eternity."

Finally, antiMusic's Zane Ewton posted the following tribute on his personal site, Lloyd Zeffler: "I am very sad to hear about the passing of one of the greatest singers in heavy metal history – Ronnie James Dio. As a member of Rainbow, Black Sabbath and his solo band, Dio, Ronnie James carved a unique legacy in rock and roll music. The power and range of his voice was never in question, and his songs – even with the dungeons and dragons imagery – were awesome calls to empower and fight for yourself. Stand up and shout! I have written about Ronnie James Dio frequently the last few years. He was one of the first shows I covered for antiMusic. It was at that show that I had the chance to meet Dio. He was gracious and sweet, even though he spent the last two hours blowing our faces off with the majesty of rock. He gave me a hug and told me to be good. Then a few years later I got the chance to seem him live with Heaven & Hell. This reconstituted Black Sabbath lineup unleashed the best tracks from their first three albums. Essential listening for any rock fan."