ok, button is the letter "I" to make a keyframe, this adds a verticy to the ipo curve at the current frame.  once you click the letter I it will ask you which to make a keyframe for, pick the one that applies.  make sure you make the keyframe for the first frame of the animation first and make sure you move to the frame you want to make a keyframe in before editing the next possition.  there should realy be a better tutorial for this. unfortunatly i am not the person to make it because my intrests do not lie in this area anymore and i am almost completely clueless when it comes to ipo curves.