I'm 22 of Portuguese descent and I've become resigned to the fact that my hereditary dark circles (I think its a pigment issue olive-toned people have in my case) will always rival those of a woman 3x or more my age. They do vary with sleep but even my perfect well-rested self looks sleep deprived to others.
I have found Make Up For Ever's concealer works. I went to Sephora and asked if they had anything that could cover it up, and the lady there matched it to my skin tone very well before I bought. It is very light, and a small drop or two goes very far - I don't anticipate using up my tube for a LONG time. I think I paid mid-twenties for it.