I have really dry hair too. I found a product by Shisheido called Tsubaki. It has camellia oil in it. It leaves my hair so soft. If you have an asian market near you, it is cheaper than at the boutique.
Try L'anza Dry Hair Formula Leave in Conditioner or even try my favorite product L'anza Straight Line Smoothing Balm....haven't we had this conversation before? I think I've posted this elsewhere but anyway......I use in even on my curly clients because there's a ton of moisturizers in it including Shea Butter!! It's yummy and not too heavy either!
Sebastian Potion 9 is fantastic, too. They used to make one called Potion 7 that was meant to be used on dry hair and then shampooed out and it was FABULOUS! But I think the concept was lost on the consumer and they discontinued it. However, you can still find some diverted product on the shelves in CVS and Sav On sometimes. I have to admit that I HATE DIVERSION but am even guilty of grabbing a tube or two myself at times because it's such a great product! It's an intestive treatment and not a daily leave in but would do wonders on your gorgeous hair!!!!!!!
Once I had a really bad color job and my hair was like straw! I seriously thought it would fall out! I actually used an egg (raw mind you) and let it sit in for a few minutes, then washed it out. It acts as a really deep conditioner. You can do it as often as you like. Just something added you could try.
I have naturally very dark hair and I used to bleach it blonde for some reason... while I was blonde, my hair was extremely dry. I like Terax Original Crema as a deep conditioner, AG Fast Food as a leave-in and every few months I would go to my hairdresser for an ionic conditioning. If you haven't tried that, it will do wonders for dry hair!