Shelly, can you post a picture of you so we know what your hairstyle looks like?
but honestly, matching jewelry has more to do with your outfit than your hair - especially necklaces. You want to find a necklace that suits the neckline of your blouse or top.
For example, if you are wearing a V-neck top, wearing a short chain or choker necklace looks wonderful becasue the V-neck sets up a sort of "frame" for the necklace. On the other side - if you are wearing a turtle neck, a long necklace sits well becasue it drapes down the front of an otherwise plain shirt.
I have a paper hear somewhere that show all the "framing techniques" of necklaces, I'll see if I can find it and post it.
As for earrings and your hair; since your hair is so long - go for some funky, bright peices that will show up through your mane. YOU can get away with this more easily than women with business style haircuts. Or just forgo the earrings altogether and focus on the necklace and some fantastic bracelelts and/or rings. If your hair is your best feature, you may not want your jewelry distracting from that anyway!