"so I was wondering if I could get one of those plug-in adapters, although I've never found them that reliable connecting computers to a wireless router."
I've had little success with these power line adaptors, and stringing a long ethernet cable was not a practical option. I use a wireless bridge/game adapter to connect my Slingcatcher wirelessly to the router. Works perfectly. (I use a Netgear WEG111, but any similar product should work.)