i disagree. you can learn quite a lot from buying a welder and just laying beads. will give you at least a slight idea about what your doing, so the poor tafe teacher wont have to completely baby you.
but i agree on the tafe course bit, absolutely essential if you want welds that have any chance of passing engineer's requirements.
its a bit late now, but late last year i bought a cigweld weldskill 250a single phase MIG.
its a cracker of a welder for the home hobbyist. uses 15kg spools, euro torch plug, can do aluminium, has all the basic adjustments, and came in under $1k.
only thing its missing is the 'inverter', but mine will never leave the shed, so i don't need it :)