Hello, list!

I've been lurking for a while, but I haven't had a reason to post yet.
I'm an undergrad who hopes to go into linguistics, but I haven't had
much of an opportunity to study the subject formally yet. I'll
probably only pop up now and then to ask questions, since I don't
really know enough yet to *answer* many.

My primary interest is in artlangs and fictlangs. Mostly fictlangs, I
suppose. I like for my langs to have a people to speak them, but am
not really all that interested in fiddling around with history. I've
created a few, and I'll probably post them eventually for suggestions
& criticism.

Now that the intro's over with, my question:

I'm creating a language for a friend's fantasy novel and she really
likes the idea of consonant harmony. The problem is that I don't
really know how it's likely to work given the phonemes I've already
chosen (which she also really likes).

I have some limited info on consonant harmony in Barbareņo Chumash and
Tahltan from Mithun's _Languages of Native North America_, but I'm
looking for other sources of inspiration. What other natural languages
use consonant harmony?