No suck thing as an LED monitor as I understand it. It is just an LCD monitor that uses LEDs for the backlighting rather than compact fluorescents.
For photos I’d avoid going for a TN film based monitor altogether. They have the annoying characteristic that the colours look dramatically different when you change your viewing angle.
The reviews here are good: http://www.tftcentral.co.uk/
I have this bad boy: http://www.tftcentral.co.uk/reviews/nec_ea231wmi.htm
23″ 1920×1080 8-bit IPS panel. It’s probably the nicest monitor I have ever used.
A good mate has the Dell U2410 which is also good.
Both were around £250 about a year ago so should be in your range now.