In 1955, he was a drummer playing part-time. He also started work at Begg's Music Store that year. In 1956 at the age of 17, he also formed Prestige Records which was used to distribute independent material from overseas labels. He purchased the Fuller's Entertainment Bureau from founder Mary Throll in the mid-1960s. Under his control, it became one of the biggest management and booking agencies in New Zealand. He had
Ray Columbus and
Lew Pryme working for him, managing Fuller's. At the time, the Fuller's roster included
Sandy Edmonds,
The Keil Isles,
The Chicks,
The Rumour, and
Shane. One of the artists he would book regularly was Tahitian singer,
George Tumahai. Warren promoted and funded
Redwood 70, the first modern New Zealand multi-day music festival. Held in
Swanson,
West Auckland, New Zealand, the festival resulted in a loss, but had a major impact on the music scene in the country, influencing future festivals held later in the 1970s. In early 1972, a syndicate headed by Lew Pryme and Glen Tabuteau purchased Fuller's Entertainment Bureau from Warren. In late 1972, Warren spotted singer
Andy Waretini on the New faces contest, and later booked him for the summer period to appear at selected holiday centres with
David Whitfield, an entertainer from the UK. In May 1974, he engaged The Bulldogs All Star Goodtime Band as a supporting act for
Daniel Boone and the Dillinger Show band on their New Zealand tour. In 1975 he was presented the
Benny Award from the
Variety Artists Club of New Zealand for his contribution to New Zealand entertainment. He was presented a Scroll of Honour and made a Life Member of the VAC in 1995 and 1996 respectively. ==Record labels==