If you use firefox with the firebug plugin you can trace request made via the XMLHttpRequest object(probably the ActiveX component in question on IE). Doing so I was able to find the content of the search at this url:
http://www.jp.playstation.com/software/search.cgi?ITEM_NAME=&
FORMAT_PS3=0&SORT=1&START=&FORMAT_PSP=0&FORMAT_PS2=0&FORMAT_PS=0&
JP_GENRE_CODE=&MAKER_CODE=&START_YM=&END_YM=&ONLY_DISC=0&
ONLY_ONLINE=0&BEST_FLAG=0&ARCHIVES=0&ON_SALE=1
If you twiddle some of the URL params you should be able to mimic the search criteria you are looking for.