Seasiders captain Charlie Adam - who so nearly joined Spurs in January - opened the scoring at Bloomfield Road with a firm penalty in the 18th minute after Sebastien Bassong had fouled DJ Campbell in the box.
Campbell then netted his ninth goal of the season a minute before the interval by connecting with James Beattie's cross before substitute Brett Ormerod netted a third with 10 minutes of normal time remaining, rendering Roman Pavlyuchenko's effort at the death a mere consolation.
The win was remarkable not only in that in brought Tottenham back down to earth after their famous Champions League win at AC Milan last week, but also because the visitors had numerous opportunities to score throughout the 90 minutes.
A couple of goal-line clearances and some superb saves by goalkeeper Richard Kingson kept Spurs out until just before the final whistle, though, as the Seasiders secured three vital points that move them up to 12th in the table.
Blackpool created the game's first goalscoring opportunity in the fourth minute when Adam won a free-kick and lofted it on to the head of Ian Evatt, who headed wide.
At the other end, Jermain Defoe was crowded out as he attempted to get a shot away and the ball went behind for a corner, which was swung in by Steven Pienaar.
Kingson met it with a less-than-convincing punch and Pienaar picked up possession, but after dancing along the edge of the box, he scuffed his shot over.
Pavlyuchenko was next to try an ambitious effort that went wide by some distance, but having soaked up the pressure, Blackpool hit back to take the lead.
Bassong wrapped his leg around Campbell as the striker ran across the box and after referee Chris Foy pointed to the penalty spot, Adam rifled the ball home beyond the diving grasp of Heurelho Gomes.
Tottenham had a chance to level things just before the half-hour mark as Pavlyuchenko laid a pass to Pienaar in the area, but the South African's shot was blocked by Craig Cathcart.
Adam then blasted the loose ball over his own bar off Pienaar as the hosts clung on to their advantage.
Spurs went even closer soon after as Defoe clipped the ball over Kingson towards goal, but Cathcart was again on hand to avert the danger with an excellent header off the line.
Adam then wastefully sliced a free-kick off target and Aaron Lennon's touch let him down after he was fed by Wilson Palacios.
An uncertain moment from Kingson led to Blackpool making another goal-line clearance towards the end of the half, this time Alex Baptiste the man to deny Defoe.
But having almost managed to grab an equaliser, Spurs suddenly found themselves 2-0 down just before the break.
Beattie collected debutant Sergei Kornilenko's back-heel and chipped the ball to Campbell at the far post, who gleefully tucked it away.
Campbell looked as if he might have been offside as he finished, but the effort stood and Blackpool were firmly in the driving seat.
Spurs boss Harry Redknapp brought Jermaine Jenas on for Palacios at the break and Spurs looked to exert some pressure from the word go at the start of the second half, with Pienaar sending a shot wide.
Campbell called Gomes into action moments later, but Tottenham were soon on the front foot again, with Jenas striking off target and Kingson doing well to save a header from Pavlyuchenko.
Luka Modric hit an effort over at the end of a nice passing move and Pavlyuchenko sent another attempt over, but having weathered the storm, Blackpool almost made it 3-0 as Adam unleashed a low drive that went just the wrong side of the post.
Back came Spurs and after William Gallas had blazed over, the visitors were twice inches away from making a breakthrough.
First Pavlyuchenko was unable to get on the end of Defoe's cross and then Lennon was too late to slide in the pass returned across the box by Niko Kranjcar, on as a substitute for Pienaar.
Kingson then pulled off a fantastic point-blank save to keep Pavlyuchenko's header out.
Blackpool's goal seemed to be leading a charmed life and they somehow managed to keep Spurs at bay again in the 72nd minute as Modric dinked the ball over Kingson but Baptiste intervened before it could cross the line.
Crouch, who had also come off the bench, then flashed a header wide but Spurs' luck appeared to be out and in the 80th minute, the Seasiders struck again.
It was two of their substitutes who combined to make the goal as Matt Phillips broke into the box, Benoit Assou-Ekotto got muddled as he attempted to make a challenge and the ball broke to Ormerod, who slotted past Gomes.
Pavlyuchenko managed to loop in a shot in stoppage time but it counted for little.