Substitute Scott Rendell's 80th minute goal at Carrow Road ensured the Blue Square Bet Premier side made a nonsense of the 85 places in the football pyramid which separated them from their hosts.
A strong contingent of 4,000 supporters, described by Buckle as their 12th man, cheered Luton to victory as they became the first non-league side to win at a top-flight opponent in 27 years to leave the Hatters manager in a state of shock.
He said: "It has not really sunk in yet. It is an incredible performance by the players.
"The most pleasing thing for me was that we defended very well and carried a threat going the other way.
"I am absolutely delighted. The fans were out of this world. We probably could not have done it without the 4,000 travelling supporters."
The giant-killing of Norwich followed a shock victory over Wolves in the third round and Buckle revealed the win acted as a blueprint.
He explained: "We took great strength from the Wolves game. It is not so long ago Wolves were in the Premier League.
"We stuck to the same plan. It is a lot easier to work in a structure. At our level, no disrespect, there is not an awful lot of structure to the game at times and it is more of a fight."
Luton chairman Nick Owen said the stunning win at Norwich was a "very, very special moment" for the club.
"We had three consecutive relegations, we were docked 40 points in a season and a half, and we've had a very difficult time," Owen told Sky Sports News.
"We came so close to getting back. We got beaten on penalties in a play-off final, lost another to an offside goal.
"Days like this really do mean an awful lot to the football club and the fans.
"I'm so proud of everyone in the team. Whatever happens in the next round this was a very, very special moment.
"We have to carpe diem - enjoy the moment."