You can make your own LED light with parts available here.
http://www.luxeonstar.com/index.php
Pick your LED and select your choice of lens and matching holder for it. I prefer the Fraen elliptical beam pattern.


I built my 1-watt LED with lens and holder in a 1-inch PVC coupler. Large childproof prescription bottle caps are a press fit and hold a clear lens on the front and aluminum on the rear with a grommet allowing the wires to pass through.

I do a lot of nighttime riding so I went with DIY hybrid lighting system. This was the reason for using a 1-watt LED. It only draws 350mA so a dynamo can easily supply it with more than enough current. Too much current if you try and connect it directly to the dynamo! It generates 500mA, which would reduce its life. Adding a battery gives that excess current some place to go and allows the LED's to continue to illuminate even when stopped or the dynamo is disengaged. Here is the circuit I use.

Switch S2 is only needed if you use a hub dynamo. S1 can be opened with the dynamo engaged allowing you to rapid recharge the batteries with 500mA. With the dynamo engaged, riding above 8-MPH, and the LED's on up to 120mA is recharging the batteries. This requires disengaging the dynamo occasionally to prevent overcharging the batteries if your not stopping very much.
Here is a photo of my test and reliability setup.

Note the modified 9.6 R/C battery pack straped to the rack. Thats 2.4 Amp hours of current available to operate the LED's for several hours without help from the dynamo.