SO-O-J and SO-O-K User Defined report Type (Do a lookup on the Report Type, it defaults to Customer type) would give you open orders and SA-M & N (same type) would work for items already shipped.  Depends which you are looking for.  With the User Defined report type, you can sort and subtotal by either Bill or Ship to State

You cannot add fields to RTM's.  I think Lynn has plans for user-defined reports that will be much more flexible.
 
For now, Crystal is excellent at creating those kind of reports.  You don't have to export anything as it reads straight from DBA data.
 
Use maintain database to browse files for fields you want.  There is no master index but it isn't too hard to find things.  You can also print all file names from somewhere in the Help index.  I keep them in a binder for browsing.
 
Of you can open the source code for screens and reports and locate file names that way. (There is a thread under the Crystal topic that deals with this.)  
 
Bill-to and Ship-to Customers and Addresses are in the BKARHINV.B** File for processed sales orders.
 
Sales Order Detail is in the BKARINVL.B** File.