Is there a website where you can "change" your hair color to see what it looks like before you dye it?

Why don’t you just use google images to see what the hair color looks like?

Do you have a good photo editing program like Photoshop, or a friend who has it? It’s pretty easy to get a natural looking preview of color change if you just open a picture of yourself, create a blank layer (color mode) on top and paint the color onto your hair. Then adjust the transparency of the layer until it blends looks right.

Try It On

@Blueroses said pretty much what I was going to say. If you dont have Photoshop you can also use Gimp which is free

here you go!
Just upload your picture.

Go to a salon with a good local reputation and ask the colorist to show you on a hair color sample board which shades would look right with your particular skin color/base.