I think Stumper's idea is a good one. I may have to check that out when I leave here. There is nothing that will actually make your hair thicker or cause it to grow faster. Even products that claim to help with thinning hair, only cause a little bit of hair to grow (if any), or just slow down hair loss. The best thing you can do for your hair is prevent damage. Use the coolest setting you can get by with on your blow dryer and curling iron, or don't use heating appliances at all. Don't color your hair. Just treat your hair very very gently.
For the dryness, a hot oil treatment once a week might help. Never helped mine, but I've heard others say it works well for them. Keeping the ends trimmed will help a lot. Use a good quality moisurizing shampoo and conditioner. Look for Dimethicone or Guar Hydroxypropyltrimonium in the ingredients. That last one might not be spelled right, but you get the idea. They're both humectants. I also use a teeny tiny bit of Jajoba oil (it's actually a wax) on the ends of my hair while it's still wet. That seems to do the most good for me. Well, that and frequent trims.