The 40-year old will become Ricki Herbert's left-hand man for the 2009/10 season after spending the last few seasons with New Zealand Championship club Hawkes Bay.
Club chief executive Tony Pignata confirmed Gould's appointment, saying, "We had huge interest in the position from throughout New Zealand, Australia and Europe but Jonathan was clearly the sort of person we wanted in the job.
"He has top-flight playing experience and has proven his ability as a coach at Hawkes Bay United. It's also great to appoint someone from here in New Zealand."
He also represented Scotland on two occasions and was a part of the national team's 1998 World Cup squad.