You can search your auctions here - buyee.jp/category/yahoo/auction/2084241343
This will help you search for your stuff on the website - www.elitefourum.com/t/yahoo-japan-search-guide/13488/1
Then you use A middle man Service which can be found by a dude on here who does it for people and best prices - @japanime
Just send him the link of the auction your after and message him to buy the things for you 