A young folk singer named Joni Anderson asked Bernie Fielder in the spring of '65 about working at the Riverboat, Fielder offered her a job - in the kitchen instead. She then met a folk singer from Detroit named Chuck Mitchell. She traveled to the US to play shows with him and they ended up getting married. Although the marriage didn't last, the folk career of Joni Mitchell took off and she would eventually play whichever coffee house she pleased - including the Riverboat in 1967 and onwards.
A tall kid with a Beatles haircut named Neil Young played the venue in its early days - both solo and with his band called Public Futilities. After this, Neil Young drove to California in a funeral hearse named "Mort" and found success with the band Buffalo Springfield. He would return in 1969 to play the Riverboat as a solo artist and recorded an album titled "Live at the Riverboat". Folk singer Phil Ochs also frequented the Riverboat, playing his unique brand of political protest songs.
Other bands to frequently play the Riverboat stage included 3's a Crowd, which were a Peter, Paul and Mary style trio who employed theatrical and comedic aspects to their act. Their lead singer Donna Warner was compared to Jefferson Airplane's Grace Slick. Folk singer Bonnie Dobson began to get famous in Yorkville but then decided to get an education at York University and only sing part time. However, she found herself back in the folk music scene in a two week engagement at the Riverboat in February of 1966. Different from the folk music usually heard at the venue, avant-garde vaudeville act The Dirty Shames enjoyed success at the venue with their jug band tunes played on unconventional instruments like the autoharp and washboard. Also, Fielder booked groups The Lovin' Spoonful and Simon and Garfunkel to his intimate space before they were world famous.