These may give you an idea.... after a (very) quick search these are the best (imo) for that sort of price.
http://www.laptopsdirect.co.uk/Grade...EN/version.asp
http://www.dixons.co.uk/gbuk/compaq-...27292-pdt.html
If you want brand new then I would look at this sort of spec.
If second hand you can probably get a better laptop but then no warranty.