When I was dying my hair blonde, I would try to find an ash tone, or something with a "drab" undertone like a green or violet.
Whenever you want brown hightlights, and don't want to have any red, you have to do a double process. There is a natural red stage in brown hair, so it would go something like this :brown, red, orange, then blonde. You would have to lift it all the way to the blonde stage, then put a brown color over that.
For now, I would try a color rinse (not the semi-permanent ones), which is pretty much colored water, and harmless as far as I know. These rinse completely out at your next shampoo. The brand I know best is Fanciful. Get one of the brown tones, that is the most like what you want. This won't, however, be able to take the red tones out. You will probably have to get a slightly darker brown rinse to cover the highlights. The only other thing about these temporary rinses, is that they rub off and can even flake off, very easily. So look out if it rains, because it will run like crazy.
Maybe Tracy will recommend a Colorshine, though I can't tell you too much about them, as I haven't used them.
HTH
