I am a petcare specialist at a petstore... and my suggestion would be to put something that tastes really bad on your hands... like bitter apple or yuck for dogs... make sure u read it and its safe for the ferret.... that might help!
Ferrets are very intellegent and fast learners, I own a Ferret as well, she does try to bite me but it isn't a hard bite, just sort of a "put me down, let me go play" kind of bite. She did this a lot when I first got her. They are very sociable animals and need lots of attention. What I did is I started handleing her more, when she'd bite I'd turn her twards me say a firm "NO" and flick her nose and put her up for a few minutes, if she tried it again I'd do the same thing but wait longer to take her out. She learned quickly that she wasn't allowed to bite so now she thinks twice before she bites.
Good luck and I would suggest you read up a little bit (if you havent already) on your Ferret. =]