Here is the basic biped setup. Add a sphere which will be your basketball.
We are going to associate the ball with the hand bone to insure that the ball will always bounce back to the palm.

 

 

Create a point helper, and align it to the handbone. This represents the target, the position where the hand holds the object. Name it HandR Target. You may want to move the point helper so that it does not sink through the mesh, since the bone is usually within the mesh. I recommend doing this step after you have your character skinned to the biped. This way you can see the exact position of the palm, so the object does not sink through the mesh to the bone. Extremely painful. Once you have the position relationship between the HandR Target and the hand bone, Link the HandR Target to the hand bone.

 

 

Create another helper, HandR Ground Target. This will represent where the ball will land, weather it be on the ground, a wall, a ceiling, someones face etc. Make it the same size as the other helper (which is the same size as the ball) so you can see the volume of the ball.

 

 

Finally, lets create a point helper that will represent the ball, call this the Right Ball. Align the basketball to this point helper, then link the ball to it.

 

Next, lets constrain the Right Ball point object to the targets. First, constrain it to the Hand R Taget. (Toolbar: Animation/Constraints/Postition Constriant) You will see the Right Ball snap to the hand target.

 

Then, position constrain the Right ball to the Hand R Ground Target. Notice that the Right Ball sits perfectly between the two helper objects. Move the hand bone, or the ground target and view the result on the Ball. Berrrry Intelllesting.....

 

Note: It is good to remember/write down which order the object is constrained. There are Weights associated with each constraint, and they are numbered (weight 0, weight 1 etc.) and are numbered according to the order they are selected. More on this later.