If you could mention the following please:
1) what size monitor you like and
2) some websites you want to purchase from
Point (2) is for those of us not from New Zealand, if a local stumbles on this thread they can always suggest a superior place to purchase.
But I think a decent place to start comparing is this monitor here
Its very good for it's price but I am not sure if it is the absolute best for under 250NZD