Here is a link to a product manufacture who sells these products.
http://www.vista-films.com On their site you can find contractors who install their products in your area.
On one note about these types of films. They can save you all sorts of money on energy but do not always work well on some types of newer windows that have UV protection already installed in the center of the glass panes. In fact it may cancel out the ability of the UV protection from working at all. So be sure to do your homework on these films.
But I do suggest this brand. I have a local guy who does all our work for us. And the clients who use their products love the results.
I live in Alabama but Lowes, Home Depot and even on Amzon.com has it. Gila low-reflective Energy Savin window film. But I suggest go to a store because each one is different in thickness and color. Its not hard once you get the hang of it to put on. We Love it. Also, I know you can order very large rolls of it from Lowes. If your wanting to do your hole house. Hope that helps:)