When IK is turned on, you can change the Parent of the goal object.  Like if you have IK turned on for Left Arm, you can select the Left Hand and use menu "Object:Change Parent." and select a prop as the Parent to the hand.  Put your prop where you want it in relation to the hand before preforming the parent change though.  When you move the prop, the hand will follow its motion. Same can be said for leg/foot relationship with IK.
Does this sound like what you're aiming for?

Hey! His nose is dry! ... Someone should lick it,  just in case. - Diego