Kevin Liverpool, 35, and Junior Bradshaw, 32, had an "arsenal of weapons" which also included hammers and a knife as they set off on a 275-mile journey to the rich star's isolated Devon home, reported Mirror online.
They were arrested at 10am outside the King's Head pub in Cullompton - seven miles from Stone's home - after a villager called the police to report two suspicious men wearing beanie hats and dark clothes.
"They got a car, they collected their weapons of choice and made their way to within a short distance of Joss Stone's house. She is an extremely wealthy young woman. Fortunately, they were not successful although she was at home," Prosecutor Simon Morgan QC said.
Police found a series of text messages relating to the plot, the jury at the Exeter crown court heard.
Morgan said a text sent on January 15 which read "Am looking to take out Jocelyn" indicated the plot was hatched several months earlier.
Liverpool and Bradshaw, both from Longsight, Manchester, declined to talk to police during interviews.