I am looking a good cheap-o (drugstore) brand "Purifying" shampoo. I need something to use about once a week so get rid of all the product buildup and whatnot.
I second neutrogena. I don't recall if it's their anti-residue, but it's in the squattier bottle, in a box.
Also, you can mix some baking soda (is that the one in the yellow box) with your shampoo. And, head and shoulders always seems to strip the junk from my hair. HTH
I use D:Fi Detox shampoo and it's the best. Seriously, I use this stuff when I come home from the beach and my hair is covered in sand and saltwater and it takes away all buildup. It's in some drugstores, and it's pretty cheap. I am yet to find a better one.