The 35-year-old, most recently with Hartlepool, played over 500 league games, scoring 127 goals for 12 clubs,
"I want to enjoy my football and help the gaffer out. Speaking about how they want to achieve brought me to them," he told BBC Coventry and Warwickshire.
"The level I'm at now I'm just looking to enjoy my football."
National League North side Nuneaton Town have signed former West Ham United and Aston Villa striker Marlon Harewood on a one-year contract.