i have a texture with a black background. By pressing the ‘add’ button i can make it so it makes the black background transparent. Well it turns out that i have to have the ‘alpha’ button selected to use the alpha ipo, and i cant use the add button at the same time. is there another way to make a black background transparent?
Well I don’t really get what your trying to ask. But if your trying to make the black texturing transparent just click on the object and then go to the uv mapping and select the face of your model’s texture then click on the alpha blend mode this will work if your texture is a .tga formated. or there should be another button called … I forgot the name of it. but it will make your texture transparent. even if it’s not a .tga formated. srry I cant explain it anybetter but I am at the school pc right now and they dont have blender. 
and for the ipo you can make object’s fade away. or make them do other cool stuff not to mention you can make them alpha but beside’s all that I will try to explain it better later 
Well I gota go right now cya all
And Remember :
KEEP ON BLENDERING PEOPLE OF ELYSIUN