Hard Candy (sold in Wal-Mart stores) has a really great concealer called Glamoflauge Heavy Duty Concealer which is actually meant to cover up tattoos, and I've heard it's comparable to the Kat Von-D concealer. It's actually the concealer used in the link that Curucar posted. It's really cheap (either $6 or $8, I forget which), and though I haven't tried to cover my tattoo with it yet (can't seem to find someone who wants to attempt to cover my shoulder to shoulder golden snitch tattoo; go figure), it works great at covering my dark circles and blemishes, which normal concealers can't do. The only drawback to the HC Glamoflauge concealers is that they come in a very limited range of colors. But, if you're lucky enough to be have a similar skin tone to one of the shades they do have, they work really well, and a little goes a really long way.
'Idiot's Lantern' Rose Tyler (Doctor Who)
Astrid (How to Train Your Dragon)
Tinkerbell (Peter Pan)
Reviving This Year:
Annabeth Chase (Percy Jackson)
Katniss Everdeen (Hunger Games)