how do i connect 3 lux emitters?

hello CPFers, I just got my first luxeons LEDs and I want to make the connections with 9AA cells. Is that the optimal quantity for the 3 LEDs and if so what capacity resistor should I use? /ubbthreads/images/graemlins/help.gif /ubbthreads/images/graemlins/bowdown.gif

Are they one, three, or five watt Luxeon Emitters? And, are you using white Emitters or one of the other colors? (In other words, we'd need the forward voltage and ideal current in order to tell you the correct resistor, if any, for 12VDC operation.)

If you're using 1-w or 3-w Luxeons you can get away with driving three in series off 12VDC without needing a resistor, but you'd need to heatsink them well - nine AA batteries may put out as much as 15VDC (and I measure 17.1VDC out of nine fresk AA alkalines once), so severely overdriving is a potential risk.