Re: Halo headlamps
What car are you putting them in? I can speak for replacing them in a '99-'04, and it's mindlessly simple... don't even need any tools (for the light itself). Remove two clips, unplug the old lights, plug in the new lights, put the clips back in.
As for the halos, like Pete07GT said, you can hook them into the running lights pretty easily since they're right there anyway. Solder would be best, but you can just use some crimp splice connectors and wrap them up in tape really well. If you've never done any wiring, this isn't a bad project to start with.
Now, that all being said. I've tried two sets of halo lights in my '00 and both of them were terrible. They looked kind of neat, but were terrible at actually lighting up the road in front of you. And both of them would constantly fog up no matter how much I dried them out and tried to reseal them.
I now have some proper OEM style lights in mine from American Muscle, and they are sooo much better than any of the halo projectors I tried. No sign of any condensation after a couple of months of hot rainy days and chilly nights. Not to mention I can actually see now. (And they look great).
Just some thoughts..