In the summer of 1973, a 20-year-old Newell joined the glam-rock band Plod as their lead singer, replacing founder member and lead singer Steve Travis (Greenfield). Plod was signed to London-based indie label Banjul Records in early 1975, and quickly began recording tracks for an album. However, contractual irregularities and financial problems at the label prevented the album from being finished or released, and the band broke up within a few months of being signed. In 2003, one track from the sessions ("Neo City") was released on a 70s glam-rock compilation CD titled Velvet Tinmine. This track was credited to The Plod, and remains the only officially issued work by the band.
Newell then joined Gypp, a pop-oriented progressive rock band, as lead singer. Gypp also played abroad and became popular in Germany's North Rhine-Westphalia area thanks to their live performances. Gypp issued one 3-song 7-inch EP in 1978, but their music was out of step with the punk-oriented trends of the UK music scene at the time and the EP received a negative review in the New Musical Express. Demoralised, Newell left the band. By his own account, he then became a "musical recluse", staying in the studio and creating new songs but not playing live gigs for many years.
In the late seventies, Newell led a four-piece rock combo called The Stray Trolleys. They recorded material in 1979 and 1980, but it was not released until 1982 after the band had broken up.
In the meantime, Newell issued his first solo single ("Young Jobless" b/w "Sylvie in Toytown") on vinyl in 1980. By the end of 1980, he was collaborating with Lawrence "Lol" Elliot as The Cleaners from Venus, a band that mostly released their work on cassettes outside the traditional music distribution channels.
By 1983, The Cleaners from Venus had evolved into a band with a floating line-up that featured Newell as its only constant. The band still primarily issued material on cassette, got signed to the West German independent label Modell Records for one vinyl album (Under Wartime Conditions) and ultimately to the German leg of RCA Records which released two albums (Going to England, Town and Country).
Giles Smith joined Newell as the only other official member of Cleaners From Venus between 1986 and 1988, and in 1987, Newell returned to performing live under The Cleaners of Venus banner. As well, while regularly releasing Cleaners From Venus material on cassette, through the 1980s Newell also occasionally released cassette singles and albums under his own name. On these solo releases he was usually the only musician.
The Brotherhood of Lizards was another Newell band that was active in 1988–89. It was a joint venture between Newell and the multi-instrumentalist known simply as Nelson.
In 1993, Newell began working primarily as a solo artist with more conventional production values. His first non-cassette solo album, The Greatest Living Englishman, was produced by XTC's Andy Partridge and had some songs arranged by Dave Gregory, and was a critical success. Commercially, it remains his most popular and successful album. It was followed by three more albums (The Off White Album, produced by Louis Philippe, The Spirit Cage and Radio Autumn Attic) and an EP (Songs from the Station Hotel) that continued to explore the same subject matter as Englishman, including the charms of rural or small-town English life and portraits of characters and scenes.
Newell has also made live appearances with The Cleaners from Venus and The Stray Trolleys in the 1990s and beyond, and has issued several post-1993 live recordings with these bands. However, studio releases credited to these groups post-1993 are actually all CD reissues of pre-1993 material previously released only on cassette. In addition, Gypp played reunion gigs in 1996, and live Gypp material – as well as Gypp demos recorded in the late 1970s – have now been officially issued on CD.
In 2004 Newell released an album of light jazz songs, The Light Programme. The album was not particularly successful commercially but his next album A Summer Tamarind returned to his usual style and was much more warmly received.
In late 2005 the British singer Richard Shelton released a jazz vocal album called Top Cat with five Newell compositions. Newell's songs have also been recorded by Miki Huber, The Jennifers, Kerry Getz, R. Stevie Moore and Alphaville.
Newell is better known to some as a poet and author; he has released several volumes of poetry (often in collaboration with James Dodds) and a memoir, This Little Ziggy, about his youth and his days in Plod. In 2007 he released a volume of reminiscences, anecdotes and historical information about his beloved Wivenhoe. He is also a weekly contributor of poetry to The Sunday Express, He now writes a weekly column for the East Anglian Daily Times (for which he won columnist of the year in the EDF/ East of England Media Awards in January 2010), performs annually at the Essex Book Festival and occasionally finds time to issue spoken word recordings of his poems.