I wlil shortly be moving from the US to Australia.  I have to decide
what to take with me and what to sell.  Some tricky questions concern
electronic equipment, as the power system in Australia is different. 
One can get transformers, but I don't know when they work and when
they don't.  I'm guessing that it's not worth moving TVs in any case
because of the different TV system, and that it's OK to move computers
(let me know if I'm wrong about these things, though).  What I'm not
sure about is stereo (and home theater) equipment.  I have a CD player
(Phillips), home theater amplifier (Yamaha), DVD player (Toshiba), and
surround speakers with powered subwoofers (Definitive Technology). 
Will these work in Australia, with transformers?  Or should I just get
rid of them over here?

PCs are definitely OK - their power supplies either adjust
automatically or else there is a switch in the back which you switch
from 120 to 240 and vice versa.  Laptops all adjust automatically.

As for an individual electronic item, the answer is really simple: 
check the back of the item.  On usually a metal plate, there is always
info regarding power requirements.  Some may say, INPUT VOLTAGE: 
110-250 VAC.  Others may say, INPUT VOLTAGE:  120 VAC or whatever. 
Most modern equipment is of the former, because it's easier and
cheaper for the manufacturer to use the same power supply in all its
units rather than having specific ones for specific countries.

Your TV, if it's a nice one, will probably have the option of
switching from NTSC to PAL and vice versa.  Likewise, you have to make
sure your DVD player has this option (most do).  Furthermore, your DVD
player may have a region code built into it.  If it does, you won't be
able to play any Australian DVDs.  Typically, Australian DVDs/players
have region code 3, while American ones have region code 1.

Unfortunately, with transformers, you see a lot of them that say, "not
suitable for use with electronic items".  This has to do with their
method of power regulation.  While a hair dryer won't fry if a little
too much juice is plugged into it, an DVD player certainly will.  The
ones specifically made for electronic equipment can get pricey, as
they also need to filter out any line noise that affects your
audiotastic listening experience.

Your surround speakers, since they aren't powered from the wall, will
be compatible with any system you buy out there, so keep those -- you
just need to find a receiver that fits your needs.  Your subs, since
they are powered from the wall, may be worthless if they can't support
240V.

A final thought:  shipping to Oz can get expensive.  Once you include
insurance and packaging materials, You may see yourself paying the
equivalent of the cost of your TV just to get it down there.  Rather,
it's probably wiser to sell it here (preferably cheap -- to me!) and
get new stuff down there.

You'll have to use your own judgement, of course, but keep all this in
mind whatever you decide to do.

Good luck!

Hi, thakns for the comment.  All of my equipment is listed as 120V
60Hz on the back.  So I would definitely need transformers.  The TV
doesn't appear to switch from NTSC to PAL either.  Each of the five
Definitive Technology speakers has a powred subwoofer built into it,
so each is powered from the wall, and I think they're 120V too
(there's also something saying 250V 2.5A on the back, but I presume
that's a fuse).  Shipping is paid for by work, so that isn't an issue.
 Basically, I need to know what, if any, of the stereo equipment is
likely to work with transformers.