Coulson, 47, is standing trial at the High Court in Edinburgh accused of lying under oath in 2010.
The jury has been hearing evidence from the paper’s ex royal editor Clive Goodman, 57, who was sacked after he admitted hacking voicemail messages to produce stories.
Prosecutors claim Coulson lied while giving evidence in the perjury trial of former MSP Tommy Sheridan when he said he did not know that Mr Goodman and private investigator Glenn Mulcaire were involved in phone hacking before they were arrested in August 2006.
Today the court was shown email conversations between Mr Goodman and Coulson from three years earlier, which the jury heard related to the purchase of a “green book” or telephone directory used by members of the royal household.
In an email dated January 24 2003, Mr Goodman wrote: “Andy - one of our royal policemen (St James Palace) has obtained a brand new green book, the telephone directory with all the home numbers of the royal family and their household staff.”
The email went on: “The standard price is £1,000.”
A reply from Coulson states: “This is fine. Didn’t I sign off on purchase of green book quite recently tho (sic)?”
Goodman said in a further message: “In December - that was £750 for the internal phone directory. Lists all the staff at BP, SJP and Widnsor (sic) with their external numbers and direct lines.
“This is the hardest to get one which has the Queen’s direct lines to her family in it.”
Mr Goodman was shown a document in court which he identified as the “£1,000 one” and agreed with Advocate Depute Richard Goddard, prosecuting, that it was “one of the items that Mr Coulson had given you permission to buy”.
He told the court he had got them from “people in journalism” who had passed them on to him.
Mr Goddard said: “Why did you tell Andrew Coulson that you got it from a copper?”
Mr Goodman said: “It’s very common for journalists to exaggerate their sources.”
Coulson is accused of falsely stating under oath that he had no knowledge of payments being made to corrupt police officers by News of the World staff while he was editor.
Prosecutors allege that between December 1 2002 and 26 January 2007 he understood that payments had been made to corrupt police officers by Mr Goodman to procure a “green book” or similar directories.
Coulson, who went on to become Downing Street director of communications, denies the charges.
Mr Goodman, giving evidence for a second day, told the trial that after his arrest Coulson suggested he would keep his job at the paper if he pleaded guilty to phone-hacking.
He said that the price he had to pay was to admit to being a “lone wolf”.
The witness said the pair met in a Wimbledon restaurant a few days after he was released from police custody and Coulson’s “recommendation” to him was to plead guilty at the earliest opportunity.
He said Coulson’s suggestion was that there could be a “way back” for him at the paper afterwards in a less public position.
“The price for that was to say I was a lone wolf and I had strayed off the reservation,” Mr Goodman said.
The court heard he received a dismissal letter from the News of the World a few days after he was sentenced on January 26 2007 for phone-hacking and he went on to appeal against the decision.
A letter he wrote to the newspaper group setting out his grounds for appeal, read to the jury, said: “The decision is perverse in that the actions were carried out with the full knowledge and support of the editor Andy Coulson.”
The letter also stated that the decision was inconsistent since other members of staff “were carrying out the same procedure”.
Mr Goodman confirmed to the court that by “procedure” he was referring to phone-hacking.
A settlement was eventually agreed by Mr Goodman and the paper, the jury heard.