Damn, i might actually buy those and get some transparent red. I could never rock them as is but i would bet they would look very good with red tint. I like how they don't have straight circle leds.
As for making them, you need to bascially make a circuit board, cut it to the shape of the taillight and throw led's in there. Then wire it up. Really that's all you have to do, but not so simple to make obviously.
What alot of people used to do before the led craze really caught on, before oem led tailights really was take lights off of semi's and hack them up and put them in their stock tails. I don't know how well it would work on an accord since it's small but it's an easy way since they are already 12 volts.
Realize if you DIY, you need a clear lens. Well, it can be tinted but if it has any sort of diffusors, like stock tails, it's just going to look like a bright stock tailight.