My last few importations were as smooth as silk from the USA and I had the complete opposite results that you have mentioned above, and I did the lot myself, and saved alot of money. Customs are experts on giving advice on importing/exporting everything and anything and give out solid advice.
I cant vouch for other states, but thats how it was in QLD dealing with Customs and staying away from freight forwarders who overcharge at every turn.. Customs was very helpful and no waiting in line or even on the phone at all up here. They make things easier for you, not harder at all in my opinion.
Importing without a freight forwarder over here takes a extra bit of effort but it will save you alot of money. Get a quote from a freight forwarder as previously mentioned, then speak with customs to get the info for doing it all yourself. That way u will know both ways and u can chose accordingly.