Gould, who recently picked up the biggest cheque of his career by winning the snooker shoot-out, only just qualified out of the group with a 3-3 record but delivered when it finally mattered at Crondon Park Golf Club in Essex.
In the semi-finals he beat Barry Hawkins 3-1 with a break of 68 in the third frame deflating Hawkins's spirit after a 95 run in the previous frame had levelled the match.
Then in the final against Maguire, Gould recovered from losing the first frame to win three in a row, with a stunning break of 139 in the match's third frame the highlight.
It was tough luck on Maguire who had topped the round-robin stage with a 5-1 record before defeating Ricky Walden 3-0 in the semi-finals.
Gould now joins John Higgins, Ali Carter, Ding Junhui and Mark Allen in the final group on March 20 and 21.
Twenty-five of the world's top players are competing in the Premier League qualifying tournament.
Seven groups of seven players produce seven winners who play in one further group in March to determine the winner who will play in the 2013 Premier League.
In each group, the top four players from the round robin stage will contest the semi-finals and final over the best of five frames.
The players coming sixth and seventh in the group will be relegated and will not feature in any further group matches and therefore three players will leave and be replaced by a further three players.
Results
Final
Martin Gould 3-1 Stephen Maguire
Semi-final
Martin Gould 3-1 Barry Hawkins
Stephen Maguire 3-0 Ricky Walden
Round-Robin Day Two
Martin Gould 3-2 Joe Perry
Barry Hawkins 3-2 Stephen Maguire
Ricky Walden 3-0 Peter Ebdon
Stephen Maguire 3-2 Joe Perry
Ryan Day 3-1 Ricky Walden
Martin Gould 3-1 Peter Ebdon
Barry Hawkins 3-1 Ryan Day
Ricky Walden 3-1 Joe Perry
Stephen Maguire 3-0 Peter Ebdon
Round-Robin Day One
Barry Hawkins 3-0 Peter Ebdon
Martin Gould 3-0 Ryan Day
Barry Hawkins 3-1 Ricky Walden
Ryan Day 3-1 Joe Perry
Stephen Maguire 3-2 Martin Gould
Ryan Day 3-1 Peter Ebdon
Ricky Walden 3-1 Martin Gould
Joe Perry 3-1 Barry Hawkins
Joe Perry 3-2 Peter Ebdon
Stephen Maguire 3-0 Ryan Day
Barry Hawkins 3-0 Martin Gould
Stephen Maguire 3-0 Ricky Walden
