I like when they go for £0.01 and £0.02 and even free on the 01 November. I stock up and make puree, other pumpkin food and pumpkin beer.
But even at £1.00-£1.50 at Tesco, they're super cheap.
Talking to my sisters in the US, who have been buying pumpkins for their kids for carving, they're paying $1-$2.00/pound at the 'Pick your own at the Pumpkin Patch' - and with the average carving pumpkin weighing 8-10 lbs or more, it's not cheap. Of course, they could also get them cheaper at Walmart, $4.00 or so, but even that is not as cheap as Tesco.