I cannot make a specific recommendation, but avoiding shampoos that have sodium LAURYL sulfate in them will go a long way towards helping your color stay fresh and true for longer. SLS is the "fadingest" of the cleansers. :sleepyhead:
Tresemme's Heat Tamer..it's cheap and it works. Also, the most recent line I've tried for color treated hair-Herbal Essences...it comes in the pink bottles. It smells great but I couldn't really tell if it helped "protect" or not but it did make my hair shiny and soft!
I love L'Oreal's Hot Straight as a heat protectant -- only $3 for a bottle! It also does a great job at eliminating static, which is a big problem for me when I try to straighten my fine hair! (Or at least it's a problem without the Hot Straight!)
They also make a Hot Curly product if you want curly hair.