10 Watt LED and LED Driver related question
I actually built myself a small lamp from one of these 10W "12V" datasheetless LEDs like this:


buy half a dozen 1W 0.5ohm resistors
bolt LED to aluminium heatsink (this is essential)
put LED in series with resistors and power supply
remove resistors until measured power in LED is about 9W (not 10W: derating it improves life and I don't trust the manufacturer)


(If the LED is the type built on an aluminium PCB, it will be a tremendous hassle to solder to it...)