For dry eyes, here are some things to consider:

1. Take flaxseed and/or fatty acid supplements. I use Neptune Krill Oil, Cod Liver Oil and DHA supplements. Here are a couple links to more info:
   http://fiteyes.com/Krill-Oil-Benefits-for-Vision-Better-Than-Fish-Oil
   http://fiteyes.com/fish-oils-for-vision
2. 

   Consume more Omega-3 fatty acids (and less Omega-6 fatty acids). Ideally the ratio between these two types of fatty acids in your diet should be around 1:1. In the typical western diet, people consume 20 times more Omega-6 fatty acids.The Omega-3 fatty acids can decrease the viscosity of tears and normalize the function of the tear glands. Sources of Omega-3 fatty acid in your diet include walnuts and soybeans.

3. Use castor oil eye drops. An old folk remedy for dry eyes, castor oil can be found in many commercial eye drops. I simply can add one drop of organic castor oil to my eyes at bedtime, but you can do it twice daily. Use an eye dropper.
4. Look into the supplement N-acetylcysteine (NAC). Some researchers believe this amino acid stabilizes tear production. The usual does is 100 mg three times a day. I don't personally use this, but there has also been discussion that it would be helpful for glaucoma and other eye conditions.
5. Check out Taran's advice about coconut oil here: http://fiteyes.com/coconut-oil