Gibbons, who was released by Doncaster Rovers last year, joined Main from Staveley Miners Welfare and found the net with a powerfully struck effort just before the break.
Gary Mundy had headed Rossington into an early lead and William Monteiro’s late goal put the icing on the cake for Ben Hunter’s men.
Harrogate had gone into the game just two points worse off than high-flying Main.
Rossington’s victory saw them bounce back from last week’s defeat at Retford and moved them to within a point of the NCEL Division One summit.
Jack Watson, another former Rovers youth team striker, has scored 13 goals for Rossington this season to help them up to third in the table behind leaders Hallam and second-placed Brigg Town.
Stocksbridge Park Steels are the visitors to Oxford Street on Tuesday in the second round of the Sheffield & Hallamshire Senior Cup.
Meanwhile, Carl Stokes has resigned as Rossington’s chairman with immediate effect.
A statement from Rossington Main FC’s committee said: "The club would like to thank Carl for his leadership and commitment to the club in his two terms serving as club chairman and we wish him all the very best for the future.
"The club will be making no further comment at this time.”