Why is it that most of the custom hair colors I have downloaded the eyebrows turn blonde?
Did the Sim get bleach on them while dying their hair that fab shade of green?

It even happens with hair that is colored in the basic 4, but the skinner/mesher didn't do
whatever it is that makes them show up in the proper color catagory
so they default into Custom. (And for the record Black hair with blonde eyebrows looks really stupid)

So.. for future reference if I start making hair (and possibly to fix what I already have) what needs to
be done to "call" the correct color eyebrows or catagorize hair color correctly? Is this something I can do with SimPE?
If I'm doing a recolor, is there a step I should take to insure my purple
hair shows up with black brows instead of defaulting to blonde?

Thanks in advance (hopefully... LOL!)

you can change the colour of eyebrows in-game by clicking a mirror and saying: Change appearence. It might not be what you need, but it helps. Or, perhaps, you could recolour some eyebrows to be purple like your hair.

I had the same complaint about having blonde hair and black eyebrows.
What I did to fix the problem was to go and find eyebrow downloads in blonde, black, etc.
Then when I was creating my sim and got a blonde hairdo and black eyebrows I just went to the eyebrow and changed it to the color I needed. I hope that wasn't confusing.
A good place for eyebrows is either here at MTS2 or Helaene.com

The reason is that most of the hair recolors started off with a blonde 'do. That color is easier to change than the others. So, when you put that hair on, it automatically makes the brows blonde, the original color the creator started off with. You can download brows, too, then you have a stash to mix and match. Or you can recolor your own. If you don't have any recolors, you'll have trouble changing the brows using "Change Appearance", since you'll get only the sim's original color or the one that goes with the recolor.

I wonder if you can just copy the maxis made eyebrows onto the blonde ones so that you'll have all the colors for every color hair even custom content. It's just an idea that just popped in my head. It's an idea, but I don't know if any one would do it, not that it's hard. Maybe hey have, I dunno.