Book ahead with Austravel possibly at least two weeks (could be a little more), but not sure of the book ahead time breakpoints to get that price, it cost me about £90 return for a trip.
The trip would take all day on a train over there, as they are slow on this route, about 60 mph on what they call the Overlander. I don't know the train price?
It's 50 minutes by air plus check in time but very very efficient check-ins, lots of staff.
What more can you ask for at that price?
The aircraft route is roughly over Dimboola given weather is permitting, where some lakes have been dried up for about 7 years.

Visited Australia in March 2006 and flew with Virgin Blue four times, greatly impressed with their service and efficiency. Would almost certainly use them again. For the price you can't beat them.

I recently flew on DJ to Adelaide. I was blown away with the Virgin Blue service levels provided from check in through to the in-flight service. I used the web check-in at home. Simply chose my seat online, printed off my boarding pass, and dropped my checked luggage off at the dedicated counter. On a short 50 minute flight, the crew were able to not only serve two rounds of refreshments, but also did it with a great smile. I fly regularly, and I found the service to be genuine, unlike my Qantas experiences. I have noticed that the seat pitch on Virgin Blue (DJ) exceeded my experience on my return flight on Qantas (OF). Much more room on Virgin.