Derby County have their sights set on matching the club record for season ticket sales.
The Rams have already sold 19,000 for next season's Championship campaign, despite their nightmare relegation from the top flight.
Appleby made a whistle-stop visit to Derby at the weekend and watched the 6-0 home thrashing by Aston Villa on Saturday.
Appleby believes the supporters can play a crucial role for Derby in the Championship and he is thrilled by their response to buying season tickets.
"It is just another incredible story about the supporters here," Appleby told the Derby Evening Telegraph.
"Our goal is to hit what we did for this season, where we cut off the sale of season tickets at 24,000, and we have got several months to go to do that.
"Even in the worst possible times from a performance stand point, the support of the fans is very heartening.
"We are moving mountains every day behind the scenes to build this club back into a winning club. I think everything will come together for next season."
Another 33,000 crowd packed Pride Park Stadium for the Villa game and once again the enthusiasm of the supporters impressed Appleby.
"I have said it before, for me they are up there with the best fans in the world, I have to believe that," he said.
"The crowd is incredible and it would just be fantastic to give them a great season next year and get back up to the Premier League.
"We are going to do everything we can to get back up and if we do, I can assure everyone that we are going to stay up."
Rams boss Paul Jewell joined Appleby in praising the fans.