Speaking outside Southwark Crown Court, the former X Factor star called on police to investigate her accuser Sun on Sunday journalist Mazher Mahmood and said her life had been put on hold by the trial.
The main prosecution witness had claimed that Tulisa brokered a deal to supply him with cocaine
Judge Alistair McCreath threw out the case after ruling that there were "strong grounds" to believe that the reporter, who was a witness for the prosecution, had lied to the court.
The reporter claimed that the X Factor judge had put him in touch with her rapper friend Mike GLC to supply him with Class A drugs. Tulisa had denied brokering any such deal.
Known as the Fake Sheikh because of his undercover disguise, he posed as a wealthy film producer called Samir Khan during meetings at a string of luxury hotels and restaurants. He promised that he could secure her a part in a film with Leonardo DiCaprio.
Mike GLC, whose real name is Michael Coombs had previously pleaded guilty to supplying cocaine. The judge ruled that he too will go free, saying the case would not proceed.
Tulisa said her life had been put on hold for a year because of the case
The strain of the past year showed as Tulisa dissolved into tears following her initial ecstatic reaction.
Standing on the steps of the court, she described how the reporter encouraged her to draw on her troubled past during a fake audition process. Tulisa has been opening about her chaotic upbringing in a rough area of North London.
She said: "This case only happened because the Sun on Sunday, Mahmood and his team tricked me into believing that I was auditioning for a major movie role.
"They targeted me when things were going badly for me and showed no mercy.
"Mahmood got me and my team completely intoxicated and persuaded me to play the part of a bad, rough ghetto-girl. They recorded this and produced it as evidence when I thought it was an audition. It was a terrible thing to do.
"As someone who has had my life ruined for the past year, I believe that this type of entrapment should not happen to anyone.
"I have not been able to work for a year can now look forward to resuming my career."
The Sun has confirmed that Mazher Mahmood is now suspended, pending an internal investigation.