If your considering buying second hand you should look at these guys
http://www.laptop.com.au
They are in richmond and although I haven't dealt with them I do know ppl who have and they seem quite happy.
Alternativley have a look at the base models (more than able to do what you want) here
http://www.pc-club.com.au/
they are in sydney so you would have to go mail order ( I bought my new laptop from them and very happy so far) - As you will in the UK for 12 months, buying from sydney shouldnt be too much of a worry
Actually just remembered somewhere that should be your first port of call
http://www.higrade.com.au/
They have 2 years international warranty including accidental damage and they are also in uk as well as melbourne.
I always now recamend my customers (and I flatly refuse to sell laptops) choose a smaller company such as the ones I listed, as I have found that dealing with larger companies when something goes wrong to be very unsatisfactory. Without fail the level of support you get is practically nil, at least with a small manufacturer they are still at the stage of trying to build their customer base and want to please, as opposed to saying "Section 84d subsection c para 4 expresly excludes the switching on of this device" an exageration (perhaps) but you wuld be amazed how often I hear from the likes of c*mpaq etc "Sorry but its our policy that if your hard drive is damaged that the whole machine has to be sent in and it will take about 3-4 weeks to have it repaired."
Take a look at the warranty from hi grade - definatley worth a look.
(Where abouts in the UK ?)