This thread might be helpful to you. It's geared more towards kittens who bite, but the ideas of how to stop it work at any age. The key to changing behaviour in cats is consistency. It will take a little time, but cats are smart animals and Dusty will soon figure out what is OK and what isn't.
The "easiest" solution is to remove play/attention/affection whenever he bites. Just give a firm "No!" (not yelling, they don't understand that) and walk away from him. Also, be sure that you do not jerk your hand (or whatever part is being bitten) away since this stirs up the prey instinct and it becomes a game.
Hope this helps. You can always post your question about biting in the Behavior forum and give us more specifics about the situations when Dusty is biting, and get more taylored responses.