when somebody purchases an item from my site it takes them to the paypal order summary page

as of now this is how the information is listed:

DescriptionsAmount
Item: NBA DailyNBA Daily $1.00 (tells them what they are buying)
Item number: 123456 (item numbers)
Item price: $1.00 (price which I know how to change)
Quantity: 1

How would I edit the Item (NBA Daily) and the Item number (123456) to read something else? Where do I find that information so I can edit it? Is it something to do with paypal that I need to edit the code or is it somewhere stored on my site thats where its pulling the data? I have been looking for the code for 2 days now and can not figure this out any help would be appreciated