http://my.smithmicro.com/tutorials/index.html

look for the section entitled Poser: Animation Tutorials, which will explain the basics of animating. Unfortunately it doesn't explain the different spline types - which affect the way an object accelerates or decelerates into / out of a keyframe (sorry , I cant think of any other way to explain it).

When searching, try to generalize your search from Poser - perhaps explanations of other apps can provide insight to the way Poser works.

Finally, I highly suggest the following book:

http://www.amazon.com/Animators-Survival-Kit-Richard-Williams/dp/0571202284/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1219893676&sr=8-1 

It won't tell you how to work Poser, but it will teach you how to see, which is just as important and translatable as learning how to use a camera.