My hair is naturally dark blonde, and I lightened it to a medium/light blonde about a year ago and have kept it that shade ever since. I thought it would be kind of fun to go darker with my hair, like maybe a light or golden brown, and, being a student, I would like it if I could get an over-the-counter color to avoid the salon prices. However, I'm concerned that since my hair is already color treated, I won't be able to choose the right product to get the shade I want. I thought about trying Loreal Color Zap to strip my color and then go darker, but since my hair has been blonde for a year, will that even work? Or should I just try to color my hair without stripping it? If so, could you recommend the best home coloring brand to try? I would greatly appreciate any advice that anyone can offer--I'm totally clueless about this stuff! Thanks a lot!

~aubs~