Tracking VAT revenue by salesperson - How?

[rodwhiteley]

we're using MOA Professional 2009 to administer the accounts of a small
professional therapies practice.
Each therapist is listed as an individual salesperson, and each treatment
session has an individual product item & description. Some items require VAT
to be charged (actually GST since it's Australia) while many do not. At the
end of a VAT/GST period we then need to reconcile the VAT collected by each
salesperson so that the individual salesperson can then pay their VAT/GST
debt to the government.
Try as I might, I can't figure out how to generate a report which displays
revenue, salesperson, date, and VAT.
It's looking like I have to do a VAT Detail report which will list all
transactions, sorted as only revenue or purchases, and then I would have to
manually assign each revenue item to the individual salesperson/therapist by
comparing customers and dates, which is bound to fail in an epic manner.
Surely there must be a way of listing the salesperson on this report?
Alternately if you can tell me a better idea, beers will be yours.
Any help gratefully received,
Rod Whiteley