try this...
if you're comfortable with installing cards into your computer, pick up a network card and install into your computer
if you're not comfortable, you can pick up a USB network adapter.
when you setup this card, you will need to setup this card to have it's own IP address.
you now have an added network port, and one that you already had in the computer.
plug one into your home network
plug the other one into the etherdongle
test your show, if it interferes with the internet, then swap the cables so that the wire going to the Etherdongle goes to the home network, and vice versa.
you'll need to setup the IP address on the port connected to the etherdongle