Once you have set up your Service Package in the Settings area, you can add it to your project within the Project Overview area.
Just click "+Add Service Package" and select a package from the dropdown menu.
Once the service package has been added to your project, you will see the price on the Project Overview:
It will also be included when you render Reports for that project. It will show up as an option on your Line Item Page, and Acceptance Page.
If you would like to create new service packages, or edit existing service packages, here's how to do it.