I assume you want a SLS and paraben free shampoo which will cleanse without drying your hair.
A simple and inexpensive shampoo can be made by mixing 1 or 2 tbsp of pure castile soap in about a cup of warm herbal infusion. ( I make an infusion by boiling a handful of mixed herbs: rosemary, camomile, and green tea in two cups of water until the mixture is halved in volume).
The real secret is not to wet your hair! Simply pour the shampoo mixture over your dry hair! Trust me :it will cleanse your hair beautifully! If your hair is really oily you can shampoo twice but using an even more diluted shampoo.
For more details and soma other solutions, you can read my hub:" A holistic approach to healthy hair"