Please provide a list of alternative ingredients to baking powder, and how much of the substitute to use in place of baking powder.
I must confess, I can't give you straight substitution amounts -- all of these leavening agents behave somewhat differently, so in most cases a straight substitution for baking soda isn't appropriate.
Ye Olde List of Leavening Agents:
Biological Cultures (Wikipedia, plus kefir whey I've seen recipes for)
All of these share the common ability to ferment flour, when handled properly.
Chemical Leaveners (Pulled straight from On Food and Cooking)
So, basically you need an acid + baking soda, or one of the heat-activated compounds (hartshorn, or one of the last four salts). In many cases a dough can provide its own lactic acid.
You can make a straight substitute 1:1 for baking powder by making your own, combine 2 parts cream of tartar and 1 part baking soda. This is essentially the same thing as baking powder, which consists of baking soda + acid.
Baking powder is used in recipes where there is insufficient acidity in the rest of the ingredients to activate the baking soda.
This type of leavening is completely different from biological leavening, and there is no reasonable substitution to be made (i.e. yeast).