Summary, because this post is unnecessarily long:
New: Compaq C731TU from Dick Smith is $750 including cashback. It fits your needs pretty well.
Second hand: Almost anything, but stick to your specs and double check for damage and other things.
Brands to look at: Compaq, HP, IBM, Lenovo
Maybe: Sony, Toshiba, Dell, maybe Samsung
No: Fujitsu, Acer, Gateway, and anything you haven't heard of
Get at least 1 GB (1024 MB) of RAM for Vista.
FS 9 will run on Vista, FS 8 should do.
I would maybe suggest the Asus EEE PC, which is small and cheap (maybe $500 or $600), but not great for gaming/FS.
Post back what you end up buying.Looking at new laptops, DSE have lots for around $850 from Compaq.
This one (the link will die soon, so it's the Compaq Presario C731TU) is $750 including a $100 cashback. It comes with 512 MB of RAM, but it has an upgrade included in the price for a total of 1 GB.
Specifications:
1.86 GHz Intel Celeron, 1GB RAM total, 80GB HDD, 15.4 inch screen, DVD writer.
The only thing that may stop you for FS is the graphics - it only has the Intel GMA 950, which is rubbish integrated graphics.
FS 8 and FS 9 should run on it, but it might not be particularly great.
Like I think I told you once at school, FS 8 should run pretty much the same like it did on your comp at home.
I have heard occasionally that the Compaq laptops have heat problems, build problems and quality control problems.
Then again, that's only some people's experience, and bad experiences always get more press than good ones so it probably okay.
Second hand, almost anything should be good as your requirements aren't huge, but don't get anything less than what you said.
The thing with computers from TradeMe is to check they haven't been dropped or otherwise damaged, like the owner spilling liquid into the keyboard.
It may not have completely killed it, but it may have damaged it and the warranty will certainly be voided.
Also add the standard warnings about buying anything second hand, blah blah
Having said that, get at least a gig of RAM for Vista - it's a bloated, resource hungry OS at the best of times.
This applies for new laptops too. Windows XP, if you can get it, is better for a lower powered computer.
Brands I have heard bad things about or would stay away from include Acer and maybe even Dell. I personally wouldn't go near Fujitsu, because they just aren't a well known computer manufacturer.
But Compaq and HP are usually pretty good. I haven't heard much about Toshiba, but they're probably okay. Asus is good, and they build a lot of laptops for the other companies anyway. IBM has great build quality, Lenovo is ok, Sony is overpriced but there isn't anything wrong with them.
FS 9 should definitely work with Vista, and I don't see any reason why FS 8 shouldn't although no guarantees.