FIeld/Table name needed

When entering an invoice, the payment method defaults based on the supplier entered.  I am assuming that this payment method must  be stored somewhere on either the ap_suppliers or ap_supplier_sites_all table but I cannot find it in either place.  Can someone assist me by letting me know where this information is stored.  Also, in the older Oracle forms, you could go to record history and see where a field was stored (or at least get pointed in the right direction), Is there any way on the web based forms to get that same information?  Thanks in advance for any help.