I have a web page at
http://www.klenger.net/arctic-fox/inverter/index.html with some info on installing an inverter.
Comment: You could get away with connecting a small inverter to a cigarette lighter style plug near the TV, but you are likely to blow the supply fuse if you load the inverter very much (over 70 watts or so). An inverter will draw about 1 amp DC for every 10 watts of AC power used, so a 70 watt load on the inverter will draw about 7 amps DC. Also, the DC voltage drop to a loaded inverter connected to "house" wiring is likely to be pretty high. All of this being the case, it's best to install the inverter as close to the battery as practical and run longer AC wires to the outlet.