Look in the contribution for ITEM based or PER item based shipping.
Ie:
Per Item Per State (or ZONE)
http://www.oscommerce.com/community/contributions,511/page,3
Shipping rate per product
http://www.oscommerce.com/community/contributions,367/page,3
Table shipping based on number of items v1.0
http://www.oscommerce.com/community/contributions,928/page,4
Shipping- Fee + x-per-kilo
http://www.oscommerce.com/community/contri...ons,1066/page,4
Good Luck