Hi,
Use BAPI_PO_GETDETAIL1 with delivery address flag as "X" and PO number, you will get the address in parameter POADDRDELIVERY. You can test it from SE37.
if you want to fetch the same using select statements then below is the explanation.
If an address number (adrnr) is not entered when a PO is created then, the delivery address is populated from the plant (from the line item). So, you have to check the fields adrnr/adrn2 in ekpo. If these two fields are blank then pick adrnr from T001W.
If the ADRNR is empty means, the Third party delivery is not required but the actual requestor address is to be considered.
So what ever delivery address maintained for a PO can be obtained directly by using FM "BAPI_PO_GETDETAIL1" in your extractor enhancement logic and fill the desired fields accordingly. if you have seperate fields like name then fill from the output parameter of bapi.
hOPE THIS HELPS YOU.
sRIKANTH.