Yep we were there from 1962 until 1973:
http://www.awm.gov.au/atwar/vietnam.asp &
http://www.vvaa.org.au/calendar.htm In all we had 60,000 service involved over that period with 521 KIA and about 3000 wounded.
As a kid I remember watching the nightly news reports telling us what was going on and though I didn't realise it at the time, I now recall a shift in the way the war and the protests against it were reported.
If you get the chance take a look at The Odd Angry Shot which is about the Australian SAS regiment in Vietman. Its good for a laugh in parts as well.
The reason recognition was much less in the 60's and 70's was that the Vietnam war was not actually a declared war and was seen at the time as a police action. This meant that awards for gallantry were not issued and even though some Victoria Crosses were handed out, unit citations for gallantry were few and far between for that conflict. It was more a government policy decision than anything else.