You guys are lucky enough to have standard flashers in yer vehicles, so you can just go get a Tridon electronic flasher and be done. My WJ has 9 pins on the flasher, and it'* about a $80 part.
It has inputs for Left Turn, Right Turn, and Hazard, 12V input, and 4 outputs, front right, front left, rear right, rear left. If it sees less current draw on any corner, it'll start flashing them quickly.
I first put in LED'* with no load resistors, and they didn't even flash at all. Bummer.
But, another place to get LEDs is www.superbrightleds.com
. I got most of my smaller ones there. One thing to look for, for the blinking side markers, make sure they're non-polarized. The nonpolarized LEDs use a bridge rectifier to make sure the voltage polarity is always correct to the LED no matter what way it'* hooked up. Bridge rectifiers are mostly used in AC to DC power supplies, hence, why they work well for this application. If you wanna make sure + is always going to + and - is always going to -, they'll do the trick.
And, on that autolumination site... I bought my HID kit from a "sister" company (i suppose), hid-sin.com. So far, they're doing good, and the kit showed up FAAAAST.
Autolumination also has what looks like 1W Nichia Jupiter 194 LED'*. Yea, man, they're bright, used one in my 3rd brake light.