Actually, that's incorrect.
User libraries should be stored in a folder called "libraries" within the sketch folder. You should not
be storing them inside the arduino 1.0.1 folder.
You can find out the path to the sketch folder by opening File:Preferences (Arduino:Preferences in MacOS) and looking at "Sketchbook Location"
If there is not already a folder called "libraries" in the sketchbook folder, you must create one. Your AFMotor folder goes inside of that.
#include "AFMotor.h" is the correct way to include user libraries (i.e., quote marks, not angle brackets)
Note that capitalization is important. The library folder must have the exact same name as the library file inside.
More information on libraries is available in our tutorial