first up congratulations on your purchase and welcome to a whole new world, weird and wonderfull as it can be, basically invertors take a 12 volt charge (battery power) and convert it to 240 volt ( mains power) so you can run things like tvs and dvd players off your battery. the more things you want to run, or the bigger the things you want to run,  the bigger the inverter and the more battery power you need. you also must take in to consideration the means to "repower" your battery if you are staying in the one place any length of time, if only overnight watching a little tv and a couple of lights ( which should be on 12 volt) then a 300 watt inverter on a single battery of say 100 amp hours will do you, driving for a couple of hours the next day will recharge your battery,  if staying longer in one place then you need a bigger (or dual system with a redarc battery isolater)  and perhaps a solar panel to recharge, you may already have an "onboard" automatic inverter, try plugging something in to a socket when not attached to mains, if it runs then you are laughing.  this is a whole world unto itself and really you need to see an auto electrician and tell him (or her) what you wish to do and he will give you the best advice. anyway dont be frightened of "the road" and all its strangers, the next people you will meet may be your best friends for life, we have yet to meet the "bad guys" after nearly 20 years of forays into this fantastic land that we call aust. and many tens of thousands of kilometres. just as an afterthought I think you would benefit greatly from joining the c.m.c.a. or caravan and motorhome owners club of australia, there you will find friends who are more than willing to help in an invaluble way, hundreds of years (collective) of experience and a wealth of information, you can go on tours with them and go to the rallies, all over australia, and when you get to a fantastic spot you are with friends, they have "helpers" like me all over the place who for no charge will "help" with breakdowns or little mishaps like busted cupboard doors or welding jobs. the website is www.cmca.net.au I know you will enjoy the company, we do.  

-- Edited by dave06 at 17:57, 2008-06-30

yep agree with that pete but one must start somewhere

bad luck worth a try you never know, as soon as you join the cmca look in the help section, maybe in the forum and see if there is a person who works on motorhome electrics, or knows anything about them, , there may be a "helper" not far from you. there is a lot of info available in there that you will find extremely interesting it would also pay to replace the fridge if you are going to free camp as they are notoriously power hungry. did you notice the special piece just on the single travelers

yes, as Dave has posted above
but you will need an inverter capable of supplying the power that you will need.

A 300 watt inverter will supply (300 watts) by that I mean it won't run a washing machine or even a hair drier, because most hair driers are at least 800 Watts plus.

Most "Mobile Homes" have 1,000 or 2,000 Watt inverters, because they are not used too often in caravan parks, but out on the road in the bush when travelling and the people in them prefere to live with a bit of luxuary, so they take all sorts of home luxuary items with them

I use a 300 Watt (pure sine wave) inverter and it will easily run a TV, fridge/freezer, computer and recharge camera and phone batteries etc.

A major thing to be concerned about is the type of Battery system the Inverter is powered by..
but that's another story

Mainey . . .