Looks like you would want the white 3 watt high-power LED. Apparently, it has a built-in current-limiting resistor, which is fine for voltages below 11V. A higher voltage would require you to add an external current limiting resistor (they say 10 ohms). For starters, just get one LED, and see if you can get a good white balance with your camcorder. I mention this because I've read that the more efficient white LEDs have a higher color temp, maybe even more blue than daylight. Now, I'm assuming you're planning on using these LEDs where it's not practical to run a power cord from an AC outlet. (otherwise, a simple AC light unit would be a lot less work) For a power source, you might try a standard 9V battery, though I'm not sure that battery could provide the 300mA of current the 3 watt LED would want. For a soldering iron, just an inexpensive model for hobbiest electronics work. I think you shoud visit your local RadioShack store and tell them what you're planning. They could suggest a soldering iron and power source.
That's my 3 cents worth. :)
Ken Hull