Products for newly dyed brown hair

I'm going to color my hair tomorrow dark brown with dark auburn highlights. Where do you find Sunsilk?  I have a Ulta and Beauty Brands store around here along with Sally's. Which color would be good for me: brunette or red? I want a lot of shimmer!  I personally couldn't tell the difference in the results in either Pantene or Brilliant. Either way my hair still faded

Congrats on your big haircolor change!  Don't worry about your hair being so dark, it will fade within a few days.  That's normal.  That brilliant brunette shampoo really has no dying ingredients in it that will maintain your color.  I use L"oreal shampoos, which are gentle and not hair color stripping.  Pantene conditioners are great (not their shampoos though). 

The sun and water in showers are the two main things that dull haircolor.  And, of course, we can't live without those!  If you are going to be in the sun all day, maybe wear a scarf or little hat.  You could also try to not wash your hair everyday, conditioning is OK daily, but washing too frequently will dry out your hair more and fade your color too.