Wilson rejoined Championship side Forest from Celtic for £2.5m in August 2013, but has been without a team since being released in May.
The 30-year-old made 51 appearances in his second spell at the City Ground, having spent four seasons at the club prior to signing for Celtic.
He has also previously had spells with Preston North End and Notts County.
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John Stollery, 58, a social worker from Nottinghamshire, was one of 30 UK holidaymakers killed by a gunman near Sousse last year.
His wife Cheryl said her husband was the most "fantastic man" and his legacy could bring about "peace" and "understanding".
The terror attack on June 26 claimed the lives of 38 people.
The attack in the resort of Port El Kantaoui was claimed by the so-called Islamic State.
Mr Stollery worked at Nottinghamshire County Council for 33 years and for the last 16 years was a social worker, working with children in care.
Mrs Stollery said she had been focussing on what good could come following her husband's death.
She said: "Hopefully [the] legacy of John's of making somebody else's life brighter and fulfilling their dreams, might bring about some better understanding and hopefully some peace.
"Acts of violence are not the answer.
"He was the most fantastic man I could have met. He made a difference in so many ways to myself, Matthew our son, to the people that he worked with."
Neil Duckmanton, Mr Stollery's best friend, said: "If there was anything he could do for anybody, he would, and he did that with me for 30 years."
He will be remembered at a service at St Edmund's Church in Walesby, Nottinghamshire.

The Glasgow-born defender, 21, was with Celtic's development squad before spending a season on loan at Dumbarton.
He moved on to Alloa in May 2016, helping them reach the Scottish League Cup quarter-finals last season.
"Obviously it is a big step up but I feel I am more than capable of making the step up," said Waters, who has signed a two-year contract.
"I played a lot of games last season and playing with senior pros helped me a lot, I got my confidence back.
"I want to play more games here and the fact the management here are willing to play younger players is what I am looking for at this stage of my development.
"The fans can expect a lot of energy from me and someone who will give their all and fight for every ball. That is my game - up and down the line all game."
Waters joins fellow defender Daniel Higgins and midfielder Alan Power as new arrivals at Rugby Park.
Kilmarnock begin their League Cup campaign away to Ayr United on Friday, 14 July, and open their Scottish Premiership campaign at home to St Johnstone on 5 August.
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The alarm was raised at about midnight on Thursday when the men became stranded after their boat lost engine power.
Three lifeboats and a rescue helicopter went to the scene. It has been described as a "major recue operation".
Mark Barnett from the Lough Swilly lifeboat described it as a community effort.
"The fishermen had gone out in their boat around Malin pier and then decided to head a little east," he said.
"The fishermen are fine but had a lucky escape.
"They had been out for half an hour when the engine broke down and they started to drift.
"They had no mobile phone signal to raise the alarm."
Rotherham United have signed former Nottingham Forest centre-back Kelvin Wilson on a one-year contract.
[NEXT_CONCEPT]
A victim of the Tunisia beach massacre is to be remembered in a church service one year on from the attack.
[NEXT_CONCEPT]
Kilmarnock have bolstered their squad with the signing of left-back Calum Waters from League One Alloa.
[NEXT_CONCEPT]
Three fishermen have been rescued off the coast of Malin Head in County Donegal.