Stoneman took to walking around the prison yard, guitar in hand, singing for staff members and fellow inmates. He did covers of Trio Los Panchos and Pedro Infante, whom Stoneman calls the "Mexican Elvis."
"I put my intelligence to better use these days," he said.
He was released Aug. 13, 2001. Two days later, guitar in hand, Stoneman dropped a hat on Olvera Street. He was determined to find an audience, anyone who would listen.
When Stoneman strolled into Barragan's Mexican Restaurant in Echo Park in 2007, manager Michael Barragan took one look at the performer and made his decision.
"I said we don't allow people to sing in our restaurant, which we do," Barragan said. "I didn't think he would be a good singer." The next time he saw Stoneman was a year later when he was hired to perform at a private party at the restaurant.
Barragan was impressed. He purchased some of the "Mateo" CDs that Stoneman had released in 2004 and invited the performer to sing at his parent's house Christmas Day. Stoneman also occasionally performs at the restaurant
"Once I heard him, it taught me a valuable lesson: that I should never stereotype anyone for the way they look," Barragan said. "I stereotyped him because he's a gringo singing Spanish music."
But Stoneman is more than just another troubadour.
When he was in prison, he saw the Oscar-nominated documentary "Buena Vista Social Club," featuring a group of elderly Cuban musicians who became international stars in the 1990s through exposure from the film.
He was so impressed that he set out to record with members of the band. He contacted a producer who had worked with the group and in 2003 traveled to Cuba to make a self-financed record with bassist Orlando "Cachaíto" López.
"It was deja vu," Stoneman said of the experience, referring to the time he first saw Lopez in the film.
It was one of the highlights of his life. He has managed to scratch out a living, but just barely. In a good week, he can earn up to $600. But lately he's been working seven days a week with little return.
On a recent day at a La Puente restaurant, after belting out a few songs, Stoneman switched from singer to salesman. He asked politely if anyone would like to buy his CD.
He left with less than $5 in tips. For the next four hours, Stoneman drove from Echo Park to Boyle Heights and back again, crashing Mexican restaurants, looking for work. On some weekends, he can drive up to 150 miles.
'He has a gift'
Any money Stoneman earns goes right back into his music. He lives in a cramped one-room apartment in Boyle Heights, filled with compositions, old guitars and books. He doesn't even sleep on a bed.
The back seat of his 1981 gray Mercedes is littered with empty Naked Juice bottles filled with water, and he carries cereal with him in case he gets hungry.
Sandi Romero, who owns a restaurant across the street from MacArthur Park, has been a fan ever since she first heard Stoneman sing "Dos Dolares" at a local restaurant two years ago. Romero said she admired his work ethic.