Here's a couple links to help you start. Depending on where you live (and assuming you won't be doing to GL), you should look at options at either Rocky Mountain Airport or Centennial Airport to start. I would suggest looking at the different companies in the links I provided and go to the airport and start talking to people. I'm not sure if the market is saturated with flight instructors or not, something you'll have to find out I suppose.

Good Luck!