I make various oil treatments for my hair. Apricot kernel oil, almond oil, jojoba oil, olive oil are all great for the hair. I add some chamomile, lavender or rosemary sometimes too.
Just put in the oil, leave in for as long as you like and rinse out with water. It's great for your hair and scalp. If you have straight flat hair, you might want to rinse with apple cider vinegar or something else though to get rinse out more of the oil.
It's very difficult to find a natural shampoo in which all the ingredients are edible -- I'm still on the hunt. When and if I find one, I will post it! There are also tons of books out there about making your own "natural" hair and skin products; however many of them are not so natural! I like MH's advice -- if you can't eat it, don't use it!