"I wanted it to be like a rock 'n' roll celebration," the American Idol fan favorite's widow, Stacey, tells PEOPLE of the memorial, held Monday at the El Rey Theatre in Los Angeles. "I was surprised at all the people who reached out about singing."
The night was hosted by Johns's friend David Foster, the legendary producer, and included performances by Idol alums Ruben Studdard and Brooke White, as well as Katie McGhie, Air Supply's Graham Russell, the E Street Band's Steven Van Zandt and Chicago's Peter Cetera.
"It's been very emotional to put together, but it has been somewhat therapeutic as well," Stacey says. "It's been overwhelming to see how much people loved him."
Not that it's been easy to say goodbye.
"I hadn't really left the house for about two weeks, and my mom finally got me to go out," Stacey says of the weeks following her husband's sudden death. "We went in a coffee shop, and the minute I went in, 'Hold On I'm Comin' came on. And I thought, 'I'm going to get Sam Moore [of Sam & Dave] to perform.' He was Mike's soul-man idol."
Monday's well-wishers, which included Paula Abdul, former Idol producer Nigel Lythgoe and former Idol contestants Mikalah Gordon and Carly Smithson, were brought to tears by speeches from some of Johns's closest friends and his parents, Jan and John Burke.
"We've had plenty to occupy us," Jan says of being busy with the funeral and spending time with family before going home to Australia later this week. "When we actually land in Perth, then maybe it will be the time to really grieve. It's all just been happening, and when we get home, then it will suddenly be more real."
At the El Rey, the family enjoyed playing Johns's large canon of music he'd recorded over the years – something Jan, John and Stacey say they couldn't bring themselves to do until recently.
"I couldn't listen to his songs for the first two weeks. It was too hard," says Stacey. "But now all I do is listen to them."
She hopes her husband's unreleased music will be made available at some point, but for now she's grateful to have his songbooks and recordings at home. "I am so lucky to have that and to be connected to him through his music forever," she says. "It's really special."
And she hopes he would have been proud of the evening they put together to commemorate his passion for music.
"I focused on what I thought Mike would want to have here, and what songs he would want to hear," Stacey says. "It was all about making a night that, if he were here, he'd be watching and saying, 'This is awesome.' "