I would like to have a hot peppered ale from extract batch. I won't be able to make an all grain, what style do you recommend? How should I add the peppers, in secondary or primary, or into the bottle?
There are many commercial examples of beers using chilli peppers.
Most chilli beers tend to be dark ales, like porters and stouts. The roasted flavor of the malts pairs really well with chilli flavor and a little heat on the palet. But don't be afraid to try other styles!
Peppers will be added either very late boil, very early on the chill, or late fermentation.
Adding chillies at one or more of these stages, insures that most corrupting organisms that may be on the chillies are killed by high temperature or the presence of alcohol.
Dry or Fresh.
Dry peppers will have less risk of bad organisms usually to the extent that they can be added like a dry hop, late fermentation. If they are whole dried peppers, crushing them up will give them,more surface are and unlock the flavor and heat held inside. Whole peppers will usually only give up the oils that are on the outside of the pepper for a milder heat.
Fresh raw peppers will have a higher risk of having wild yeast or bacteria on them. These would be best to add late boil or on the chill at about 180°F. Whole peppers will also only give hints of the flavor and heat. Puree or cut up the peppers for more heat and flavor.
Depending on the pepper a little can go a long ways, it may take a few batches until you get what works for your liking.
All in all chilli peppers can follow the same recommendations as fruit or spice additions, as far as how and when.
Hope this helps.