You DEFINITELY have to use a pressure canner for pumpkin, and it has to cook a good amount of time, because it is so dense.
The best way to cook fresh pumpkin used to be to cut the it in half, put it upside down on a foil-covered baking sheet, and cook in a 350 degree oven until it's soft and mushy. You then run it through a food mill, and go from there with the instructions you'll find on the above web sites.
I don't bother with fresh pumpkin anymore, but I'll bet you could prepare it the same way as above in the microwave...thing being, you could only do one half at a time. If I were faced with several pumpkins to cook, I'd use them both.
Be aware that your fresh pumpkin will not be orange like the canned product. This is because what you get in a can is not pumpkin...It's butternut squash. That doesn't mean your pumpkin won't be delicious...
I's just tan instead of orange.
I have had a couple of gardeners give me what they called "punkin". One turned out to be a Hubbard squash (BIG). The other, given to by my neighbor's maid's husband, back in the mid 60's when I lived on the bayou, was a big, green and white striped thing with a thick neck, called a Cushaw. I had no idea how to cook it, so I cut the whole thing up in 2" cubes (very hard cutting without a good knife) and simmered them in a pot with a little water. It took me hours to fix, but turned out sort of OK. The next time I talked to Naomi, the neighbor's maid and my forbidden friend, she said she would have gladly cooked that punkin for me.