I have similar problems.  I have two furballs.  "Tarball" is 2.5 year
old fixed male, first in the apartment.  "Ciggie" is 8 yr old fixed
female, runt, submissive, lotsa love.

The only thing that's outright unacceptable in kitty-behaviour is
"more-than-playing" violence, right?  i.e. Biting that breaks the skin,
etc..

It took me about 16 months to train Tarball off'a attacking me -- after
I brought him home from the local shelter.  He's a real spaz case.  I
honestly think he has some kind of kittie-ADD.  Kittie ritalin would be
great -- but lacking that, I just use copious application of the
water-spray bottle when he attacks.

I also re-enforce good behaviour whenever possible..  Lots of special
petting, talking to, etc.. for the evil wee bastard.

I've applied negative and positive re-enforcement to modify Tarball's
extremely aggressive behaviour.

I'm occasionally worried that I am too harsh when I discipline him --
but then again, I remember the first 6 months, when I would be bitten
badly enough to draw blood on MY face, head, hands and arms at all hours
of the night.  (and day).  .. no kidding, he'd attack me at 3:15 a.m.,
while I was sleeping .. and draw blood.

Spray the sh.t out of your Tom.  Teach him that you love him -- and that
trying to kill the other cat(s) or you is not acceptable.

You must be consistent.

No giggling when he attacks some human friend.  No petting to stop him
attacking the other cats.  Negative re-enforcement can be yelling,
water-spraying and physical pushing.  Not slapping or punching --
picking up and removing from the scene of the crime, eh?

Works for me.  Good luck to you.

-- Scott.

There is a web based behaviour forum that will give you some advice
to help change your cats behaviour . I will e.mail you the details.
 Alison

Try putting a halter on him for short periods of time. Some cats are
fine in a halter, but some think they can't walk well with one on, and
you can use that as a restriction. We do this with Chase. When he
starts attacking or stalking Kira, I put the halter on him. He
instantly becomes Angel Boy. He walks okay, but he thinks he can't run
and jump. So he just curls up for a nap instead. Or gets really
friendly.

He doesn't do it as much now that we have a playmate for him (whose
bigger than him), but he does still do it occasionally, and out comes
the halter. we call it the Twisted Halo.