Haven't actually heard them, but I have heard nothing but GREAT things about those little vox modelling amps. Trademe is definitely the place to pick one up - they are pretty cheap to start with ($500 for the smallest one?) but you can occassionally pick up a second hand one on there - bargain.

Also, there's a line6 flextone III going for $1000 which I'd say could be negotiated to $800 or so as he's not getting any bites. More than you want to spend but if you want a "do everything" amp at a great price, these are so good that many studios now have one. While it's not as good as a Marshall stack or Vox AC30, it gives a good approximation of both those, plus about 30 others. If I was starting out these days, I'd save my money and get one of these, though the Vox may be just as good or better - they're kind of covering the same ground, so try both first. Vox is probably going to be more in your price range though.

Crate amps (at the rock shop) are also extremely good value for money as they're virtually unknown in NZ, definitely worth a look.

In terms of shops, Guitar Gallery are the winners hands down. I wish we had one up in Auckland. They know their shit (they actually build their own line of amps and effects) and are more interested in music than bottom lines - unlike almost every other shop in NZ, which is one of two giant chains.

A bit of topic as this is well out of your price range, but for those more experienced playas who are looking around for a great "do-all" tube amp, Yorkville has come out with a brand called Traynor, consisting of a 50w, 30w and 20w (I think) in shiny colours. They are absolutely beautiful - lovely warm Vox clean and a gnarly little overdrive that goes right up to a ripping distortion - I was playing big warm crackly chords on low gain, up to Queens of the Stone Age riffs on full gain. And accutronics reverb, if you please. And at $2000 a pop, they're not prohibitively expensive for the sound.

Me, I've fallen for the Hughes and Kettner Duotone, but at $4000, it'll have to wait until I sell a kidney. They eat Mesas for lunch and pick their teeth with Marshalls.

Fuck I love amps.

Totally- comb through Trade Me, see what you find... as much as I love looking at new amps, I've had way more luck shopping on the second hand market. And luck is important, because the thing with buying used is that you've got no warranty support if things go wrong... if a used amp catches your eye, seek out some advice before you put your money down on anything. I wonder how the Consumer Guarantees Act protects purchasers of pre-loved goods?

http://goodvibrations.co.nz/products.php?p=Menu1_1_4&t=1
There you go - and only $400. Bargain.