When Walsh was aged 12 he started to play the piano and by the time he was 14 he wrote his own songs; he enjoyed listening to groups like The Charlatans, Oasis and Jeff Buckley. A shy and lonely personality, he looked for artists that had, or have, an influence on the musicians of his generation.
Eventually he got attracted to artists and bands such as Neil Young, Bob Dylan, Nick Drake and The Beatles. Walsh was so impressed by the music of Tim Buckley, that he decided to name his own band after the title of Buckley's 1970 album Starsailor. He met fellow band members, James Stelfox and Ben Byrne, when he studied music at the Wigan and Leigh College in Wigan.
Some rumours said that Starsailor members Ben Byrne and James Stelfox were in another band. One day,when their vocalist did not turn up, Walsh asked them if he could sit in with them and sing for this rehearsal. This was the first incarnation of Starsailor as a band. Walsh decided to play the guitars for the band after the "frustration over not finding a musician right for the group".
On 31 March 2009 The Sun announced that Walsh will appear in the movie adaptation of controversial rock and roll novel Powder by Kevin Sampson. He will play the role of the singer of The Grams. On 3 April 2009, Starsailor's website administrator, confirmed part of the information stating that "James had been in talks with the Powder author about providing the vocals for the actor in the film" and else adding that "James himself won't be acting or appearing, but might provide the vocals for the songs in the film". The film will be released in Autumn 2011, after a premiere on 19 May.
In 2009, he started recording his first solo album, working with American songwriter and singer Suzanne Vega. His first solo EP, Live at the Top of the World was recorded in Tromsø with a chamber orchestra from Norway, and was released in November 2010. He has also contributed to a mini-album Robotic Heart Foundation by Nikolaj Torp Larsson and Andreas Olson, after he met them at a studio when working on a film. Larsson and Olson have continued to work with Walsh on his debut album.