If looking for around a metre in length, any of the Antaresia species (Childrens, Spotted, Stimson) will fit the bill in terms of size, and mostly are well mannered and good choices for 1st timers.
Our first was a Spotted - She has been extremely well behaved, very placid, never bitten and loves being handled by everyone including our children. Like all snakes, you can get a devil, and many will be snappy as youngsters. Regular gentle handling usually quietens the majority of them down (except the odd devil!). Antaresia, being small means that bites when young are barely felt, and even as an adult are not as major as some of the larger species.
If getting a hatchy your first and easiest enclosure would be a 7 litre Sistema brand tub from Coles or Woolies (around $9) with some ventilation holes in the lid (look around this site for examples). Put a 14w heat matt on top so that 1/3 of the tub is over the mat, add a simple switching thermostat and for around $50 you have an enclosure big enough to house an Antaresia for the first 12 months of its life. Don't be fooled by pet stores who will tell you that you need every piece of equipment under the sun! Ask questions on sites like this one - there is plenty of advice around.
Use this first 6-8 months to research and learn about what type of permanent enclosure you might like for your snake once it gets older - gives you time to look for what you know you want, rather than what you think you may want. Also buys you time for something to your liking to come up at the right price - or even tackle a DIY job on an old TV or entertainment unit conversion (we often scout the charity stores and see good cheap cabinets that would be able to be converted for minimal $$).
Having the Sistema tub and mat will never be a waste......This will be unlikely to be your first snake (if you are like most of us you will become addicted and get more!!) so you will have a spare 'click clack' at the ready for one of your next snakes.
Hope this has provided a little insight.