Immigration to Australia - Find Place and School for my family?

Here are some links that you can look at.
They will give you a good idea how much your rent will be in certain areas of Sydney.
http://www.homehound.com.au/
http://www.domain.com.au/
I also put a map of Sydney so that you can see where you are thinking about renting and if there are schools nearby.
http://mapad.terrapages.com/MapAd/Sydney-NSW.html?OVRAW=map%20of%20Sydney&OVKEY=map%20of%20sydney&OVMTC=standard&OVADID=3744041041&OVKWID=39256656041
To find a good school,your best bet is to google schools in the area you are thinking about living and read up on their websites.
Some schools in some areas have a waiting list,so you may want to think about enrolling your child into a few schools before he gets here.
I had my daughters booked into 3 different schools before we came to Australia,and it turned out that if we hadn't have enrolled them into the school they both ended up wanting to go to before we got here,there wouldn't have been a place for one of them.
I hope I was of some help.
Take care.

for accomodation look at www.smh.com.au
most state high schools have an art department , he will need to go to a private art school when he is 18

You cannot just move to sydney.
Have you applied for a migrant visa?
You cannot move until your migrant visa application has been processed.
And you dont always know when that will be or how long it will take.

you really need to do your own research about this... australia's a massive country, you can't just rely on people on the internet who've never met you to tell you where to live