I've done a tiny bit of research on various oils that are used on hair. I thought I would present the modest amount I've learned and let the rest of you add on with your information. This should help people decide what oils might work best for them and why.
One thing I know about coconut oil is that it is said to help prevent protein loss when washing hair. Therefore it seems a good oil to use in your hair the night before or at least as a pre-treatment about an hour before shampooing.
As far as different oils working better for certain hair types, I wonder how much of it has to do with how the oils works on the hair. Some oils penetrate the hair shaft and other oils sit on top. These are the oils and qualities that I know so far.
Striaght chain glycerides that penetrate:
Coconut
Olive
Avocado
Palm Kernel
Camellia
Sweet Almond
Castor Oil
Oils that partially penetrate:
Meadowfoam seed
Polyunsaturated oils that sit on top of hair:
Jojoba
Sunflower
Grapeseed
Sesame
Broccoli Seed
If one is wanting an oil to fortify the hair strand somewhat, then it seems one of the oils in the first classification might be best. If one is trying to seal moisture in or keep humidity out, then I wonder if one of the oils in the latter class might be best. If one wants to do both, then it seems that a light oiling with an oil in the first class, followed by a light sheen of an oil from the second class might be what is called for.
Anyway, I think this might give you all some things to consider when figuring out how to use oil for your hair routine. Anyone with something to contribute to this thread is encouraged to add what you know. If we get enough of a body of new information I will try to incorporate it into this first post so that people searching for this information won't have to wade through a long thread to find what they need.