Lots of people ask me for informational interviews. Sometimes they seem to think they need to become someone else, to go back to school, to be of value in the sustainability community.
In my experience, though, the field is still so new and the degree programs in sustainability so scarce, that most people can parlay their interest in sustainability in a host of different ways.
So answer these questions:
--What do you love to do that you're also good at?
--What type of work environment is best for you (e.g., individual consulting firm, large company, etc.)?
--What industry do you have the greatest affinity?
Make a diagram of these relationships and consider how you might fit into the sustainability movement. Do informational interviews and ask people where your skills might be of value. And ask each person you interview to suggest 2-3 other people.
This is a process of self-discovery but it is well-worth the time. When you find a way to express your deepest values in your work, you have a calling, not just a job.
Warning: It's addictive. It may force you to make big changes in your life!