accounting example for purchasing inventory, and physical varience

I know in Sharon Foga's book on accounting there is a nice tutorial for
doing a sale.
Has all the steps to configure ofbiz, including tax auth etc.
Is there any examples of purchasing inventory, and adjustments.
My boss does not want to use sales order in ofbiz. He wants to use physical
varience via service from our POS. He does want to use the
requirements->P.O.-> receiving to get inventory in the system.
My next task is to do some reports Cost of goods dsold was top of the list.
I am thinking of using inventory counts for begining +purchases - ending =
COGS. In any event if any one knows of tutorials let me know, if you have
had to set up Ofbiz to record adjustments in inventory, or receiving maybe
you could let me know what needs to be configured in the Chart of accounts
etc. I can try to figure it out by looking at the example for sales.

Joel Fradkin