140098 Shipping Script Needs

Ok This is what I need....I have an OSCOMMERCE template script. It is a standard template you see on the template websites, not a big deal. The pre installed shipping script is not working the way I need it too. What I need is a script that allows me to put in different prices for different items for the cost of shipping, and adds it to the total cost for checkout. Each product I have has a different shipping cost due to weight or size etc.... The pre-installed script will not allow me to do this. We ship using UPS, FEDEX, USPS Priority, AND DHL, So I would need these options and have it accept any price for shipping I put in. So I hope I was clear, I need this done like yesterday..lol Thanks for your time