What type of photography do you want to do with LEDs? LEDs don't really produce that much light, they are tend to be very directional and harsh, also color balance can be an issue.
To give you an idea here is a LED light designed with photography in mind.
VariZoom | S-2010C Dimmable On Camera Light - LED, | VZ-S2010C
40 watts of luminence at that outragous price. You can buy a alien bee stobe unit for about the same if not less that would walk circles around this thing and not even break a sweat.