Well my Lexus is up for sale up the moment (free plug!). It is advertised on Carsales.com.au and Carpoint.com.au. Also went in the Age for 2 weeks and is in Unique cars.
The amount of ridiculous emails I have had from people from those ads is not funny. Emails with no introduction or sign off and read:
"does it have alloy wheels"
"does the sun roof slide"
"would you take 20K when it was up for 30K"
I now have a couple of people seriously interested in it but even on here I got offers for a straight trade from people when I clearly put that I wanted to down grade to release some equity for a house deposit.
Be prepared is all I can say!
All up advertising was about $350 from memory as whilst the websites are free or under $10, the mag and Age cost a bit.
Having said all that, I have had several genuine enquiries from here including Swordfish so it is not all bad.
Oh and can you let me know details of your car as I am looking for a Skyline.