Legality of HID headlights

[cali yaris]

There are things out there saying you can't modify your headlights to HID unless the car has factory HID (which I also CAN'T find a general list of such cars - as there are 2004 Mazda's that have HID's factory installed)

That's correct. Park your car facing a wall at night and turn on your headlights. Do they come up slowly or are they immediately full brightness? The former is HID, the latter is a regular (halogen) bulb.

I wanted a light that would classify as a "SHADE" of white, but higher on the color temp scale more towards pinkish (30,000k).

100% ILLEGAL in California. (but that doesn't stop a lot of people from running all sorts of colors). The interpretation of the color is also at the discretion of the officer giving you the ticket, as well.
Further, any HID installed into a reflector housing (which the Yaris has) as opposed to a projector housing is going to be producing a VERY bright light, that some oncoming drivers may find TOO bright.