Hold up for a minute.
Get a USB extension cable, like this one
. Now take a medium sized mixing bowl (round bottom) and flip it over. Get some aluminum foil and cover the bowl with about three layers, molding it tot he shape of the bowl (making a parabolic dish out of the foil). Once you have it made, take the foil dish and cut a hole in the bottom of it big enough for the female end of the extension cable to come through. Put it through, making sure that the foil does not touch the metal of the cable end, then tape it there. Hook the cable up to your computer and hook your adapter up in the dish (use enough tape to hold the adapter up straight). Now aim it at your router and see if you don't get a great signal.