for 250 alesis mi mk2 powerd monitors are great,
if ya can go to the 500 mark id look at some of these:
http://www.turnkey.co.uk/tkweb/stock...mp;context=WEB
genelac are one of the best monitors on the market
about £512 for them though

http://www.turnkey.co.uk/tkweb/stock...mp;context=WEB
tannoy are great monitors also,

www.turnkey.co.uk
go there and dont be so lazy, lol,
all of the above are good for the your budjet but if ya can extend go for either YAMAHA MSP-10's or DYNAUDIO BM15A or similar.
MSP10's are te industry standard and DYNAUDIO are just damn good monitors,

Dynaudio or genalec are the best money can buy