You may be able to find them at samsungparts.com, amazon.com or ebay.com. I don't know of any Authorized Samsung Dealers that stock them.
I tried to find one available for sale, but they come and go online relatively quickly.
I'm trying to locate a source to purchase the WIS08BG LinkStick for a LN52A750 LCD TV. I've searched the Internet and have not found a single one. Does anyone know where I can buy the WIS08BG?