Mate, what area are you in, if you are near the city, check these places out:
1. 227 Broadway, they have a back entrance on the back alley way, not much traffic, very discreet and no flashing neon sign either.
2. Sydney Baby Massage, located on a quiet street, only the locals and punters will know.
3. St Peters at May Street, also on a quiet street, not much foot traffic.
Cheers