Report for Purchase Orders

I'm looking for a way to create a custom report for Purchase Orders that will allow me to include data for Cost Center and GL Code.

Currently, if I create a custom report using 'Purchase', I'm given the following fields to include:

PO Number
PO Name
PO Terms
Ordered Date
Required Date
Received Date
Shipping Price
Sales Tax
Price Adjustment
Total Price
Payment Terms
Shipping Info
Shipping Comments
Ship To
Bill To
Include Shipping
Sign Authority
PO Status
Pending Status
Purchase Requestor
Purchase Category
Vendor Name

Again, I want to include info for Cost Center and GL Code. Is there a way to do this?

Thanks,
jhowe