I need a usb extension for my Sony wifi adapter so that I can receive a better signal because my router is at the back of the house.
Yes, definitely - we can help get your USB wifi adapter up to 10 meters away from the BluRay player (and thus 10 meters closer to your wifi router).
http://plugable.com/products/usb2-10m/ will work for that scenario ($13.95). It pushes USB to 2x spec distance, which is a problem for some devices, but shouldn’t be for that wifi adapter. Just post back here if you have any trouble.
Hope that helps. Thanks!