Clairol Balsam color. I just used it, and the color looks really natural. It's just $2.67 a bottle at Wal-mart. The catch you ask? It doesn't come with conditioner, but...you can use whatever conditioner you have at home after coloring your hair, just leave it on for at least 2 minutes, 5 if you want more conditioning. I'm trying to stay on some sort of budget, so I'm glad I tried it.
This web-site carries it, just not in every color. You're better off going to Wal-mart, much cheaper there.
http://www.drugstore.com/products/pr...sam_color_blac