35-year-old Kevin Liverpool and 32-year-old Junior Bradshaw drove from Manchester to Stone's home in Devon. In notes uncovered by police, they planned to behead her because of her links to the Royal Family.
The duo had scouted Miss Stone's home and were on their way to attack her armed with the sword, three knives, two hammers, masks, gloves and a hosepipe
But they were arrested in Cullompton in June 2011
Suspicious residents had called the police having spotted Liverpool and Bradshaw's badly damaged car in the area
Speaking outside the court Joss Stone's mother, Wendy Joseph, said the whole family was just relieved the trial was finally over.
Joss Stone issued her own short written statement saying:
I'd like to thank everyone for all their support and kind wishes. I am relieved the trial is now over and that these men are no longer in a position to cause harm to anyone.
When police first discovered the pair they told police they were lost and were trying to get to Bristol. But officers became wary and quickly discovered the cache of weapons in the boot.
A search of the one-bedroom flat Bradshaw and Liverpool shared in Manchester also recovered a self-cocking crossbow and a BB gun.
Kevin Liverpool is starting a life sentence - with a minimum term of 10 years and eight months while his co-defendant awaits sentencing, pending medical reports.
You intended to rob her and kill her and dump her body in the river, according to your words, and then leave the country with your accomplice Junior Bradshaw. You had no reason to target her except that she was a wealthy young woman as she was a successful singer. You assumed as she was a friend of the royal family she would be able to give you money. It may have been, to use the colloquial, 'a crazy scheme from a crazy person and must be likely to fail' but when you decided to travel from Manchester to Devon you intended to carry it out.
Watch Emily Morgan's report in full.