What kind of pumpkins did you get? You really do not want the large orange Jack O'Lantern ones as they don't have as much flavor. Most people when using whole pumpkins use the smaller Sugar Pumpkins or even butternut squashes.
Anyway, what you would want to do is cut most of the "meat" out of the pumpkin, dice it into cubes and then roast it in the oven for 30 minutes to caramelize it somewhat. You could sprinkle brown sugar over it before roasting to, in order to add a little more flavor.
Then the pumpkin is added to either the mash or to the boil.
The best way to prepare pumpkin for the mash is to roast it until it is soft. I suggest cutting into quarters and cleaning and baking in dish at 350 for 60 minutes or until it is soft. (I roast mine on an open fire). Then allow to cool and peel and cube into about 1 inch cube. I use 5 to 7 lbs in a cereal mash for a 5 gallon batch.
After fermentation I add more to secondary. For this I use about 2 to 4 lbs with 2 quarts of water and I boil it until it is mush. I add hops and spices and then cool and add to secondary.
I second the notion of using pie pumpkins. The regular carving jack o lanterns have hardly any color or flavor. The meat in pie pumpkins is a much more pronounced orange.
So I prepare my pumpkins by cutting them up into ice cube sized pieces. I place those on a cookie sheet w/rim. Bake them for an hour at 350°. I look for the edges to get dark brown. Add a cup or 2 of water to each sheet so the pumpkin doesn't dry out. Most of that water will get absorbed into the pieces.
Personally, I put my pumpkin pieces into a mesh bag and add them at the start of the boil. I've heard and read that some people mash the pumpkin. I've always boiled it with good results. By using the mesh bag I can pull out 90% of the pumpkin so I get hardly any trub. Just the normal amount of trub from the yeast.
I brew more pumpkin beers than just about anything else as most everyone I know goes nanners over it around this time of year.
I get whats called sugar baking pumpkins(they are not orange like traditional ones, but not white..kind of a pale orange but they are AWESOMELY sweet!).
The only place I have found these is up in the mountains of NC on the side of the road stands.
I cut open, gut it and cut it into quarters. Tin foil on a deep baking dish and into the over at 350 for an hour and a half. The pumpkin will literally start to look like its deflating and the skin will start bubbling.
Take it out, let it cool and the pumpkin meat should just be very soft. Seperate it from the skin, mash it up. Pour any of the clear pumpkin juice from the baking sheet right into the mashed up pumpkin. That pumpkin juice is liquid gold man.:rockin:
For the mash in, I usually mash in a little higher temp-wise if the pumpkin is 100% cooled..Mash in my grains(no doughballs) and then just plop the pumpkin on top of the grains so the strike water is just over the top of the pumpkin. Let it sit for 45mins, stir gently and 15 mins later, collect my first wort runnings.
I batch sparge and stir more on the sparge than on the strike in with the pumpkin involved, but still dont get many stuck sparges using whole pumpkin. Canned pumpkin is another story. That stuff disintegrates into the mash and sticks my sparge 75% of the time.
I always hit my SG with this method and never had an issue. Finding GOOD whole pumpkins are a pain off season.
All good suggestions. I think you should use a proven pumpkin recipe. I just brewed Thunderstruck Pumpkin Ale from this forum, it tastes great even before carbonation. Brew Your Own had five recipes in the last issue. Adding pumpkin to a pale might be good, but you have a better chance with something well established, IMHO. Do let us know what you decide, and how it works.
So should I go with an amber ale? I have a recipe that I was going to just add pumpkjn to. I guess I'm asking is will the pumpkin add to anything or is there preferred ingredients (besides the obvious)?
I think you will find that the pumpkin alone will add little flavor, just some body. Most Pumpkin Ales use spices too. There was a great article in the last (not current) Brew Your Own magazine. There are also several 5 star recipes in the recipe section of this forum. Many brewers are making pumpkin ales at this time of year. Read those successful recipes before formulating your own. Or just use a proven recipe, and decide if you want to modify it next year.