I live in The England!
British citizenship is quite hard to get i believe. I know you have to take a ridiculous exam which you need to know the queens birthday, national holidays and slang words and stuff - this is true!
for universities and colleges look at http://www.ucas.ac.uk/
and you can apply and search for courses through there.
good places that come to mind for economics are LSE, Cambridge, Oxford, Warwick, places like that. Any uni in the top 20, especially those in the Russell group is a good bet. google Times university rankings. I don't know what the fees are for non EU citizens; my friend from HK has to pay £12000 per year, which compared to my £3450 per year is quite high.
There are no real "community colleges" in England because all uk universities are semi state funded.