Is this possible - please help

I have been messing with this for hours trying to get it right and have yet to be successful. Any help would be appreciated.

All my items are basically identical as far as size weight. I would like to offer choices.

US options for ONE item I would like to be:
-$6 Priority or
-$4 Media

Overseas options for ONE item I would like to be:

• CANADA, $7 airmail.
• EUROPE, $13 airmail or $8 surface mail.
• JAPAN, FAR EAST and AUSTRALIA, $15 airmail or $8 surface

Now for each additional item I would like to add $1 and have the cart do the math if possible. For example 3 items (in US) would be $8 ($6 for the first, and $1 each additional), not $18. Get it?

Is this possible? Or if not, what would be the best way to go about getting the results I want. I'm trying to avoid customers having to email me to get shipping totals etc..

Messing with it for more hours I have almost accomplished my goal using the "table rate" module. Now the onlt problem is that it applies to all items in all areas of the world.

So now I want a seperate one for overseas etc...

I'm not sure this is possible because it seems like the cart would have to somehow know that the customer was overseas. Even if the customer puts his/her overseas address when registering, would the cart still display the US rates for them?