Trouble with adding shipping to ecart

Hello, I've had the e-cart and data assist package for adding ecommerce to my site. Ive have the ordering part complete and functional but Ive not been able to figure out how to place shipping for each items. At this time, I have one flat rate for everything with is not the way it should be done.

I need help. I've watched the videos and read tutorials and Im lost.
Maybe I'm not reading the correct material.

This is what I'm trying to achieve is...
The shipping should be based on the price.
Example orders under 50.00 would be $5.00 shipping
Orders of 50.01 - 100.00 would be 10.00 in shipping
Orders of 100.01 - 150.00 would be 15.00 in shipping
Any orders over 150.01will require a quote.

How would I achieve this?
Can it be done in the ecart or do I have to form a data base?
If someone could let me know which avenue to take and
where the instructions are that would be most helpful.

Thanks in advance. Sam