I second the saw palmetto suggestion. I started it in November, waxed at the same time, and haven't had to since. I have never had black hairs or thick hairs, just a little more facial hair than I prefer. The growth has slowed considerably and I haven't waxed since. Saw Palmetto does alter your hormonal balance (balancing), and I did experience a couple days of spotting. There are warnings against using it if you are pregnant or nursing, and suggestions that it may mess with some hormonal medications (like BC pills). I don't take saw palmetto every day, but often enough.
The following is from the University of Maryland Medicine site. I have included a link below. The site has a lot of other information on conventional treatments as well.
Two laboratory studies have shown that an extract of saw palmetto (Serenoa repens) may inhibit androgen activity in human cells. More research is necessary, however, to determine whether these laboratory findings will have any practical applications in terms of treating hirsutism in humans.
Professional herbalists may also recommend the following herbs to relieve the symptoms associated with hirsutism:
Black cohosh (Cimicifuga racemosa)
Goats rue (Galegae officinalis herba)
Fenugreek (Trigonella foenum-graecum)
Chaste tree (Vitex agnus-castus)