There's a lot of information on finding angel investors on this site--entrepreneur.com--on plans.com and on many other sites as well.
You do have a problem, though, unless there's some special angle you're not sharing, because investors are not generally interested in service businesses, at least not as much as products, because there's no leverage.
The investor makes money when the value of your business multiplies, and it's hard to multiply services. Are there products involved? Proprietary technology? How would the investor get his or her money back, and make money, on a janitorial service (green, or not)?
Investors want to make money. How are you going to give them return on that investment?
As for special funding, that's a different question. Like you, I have the impression that there are more public funds available for greening than there used to be. For federal money, start with the SBA at www.sba.gov. Check with your local Small Business Development Center as well (search for SBDC and you can use the list at http://asbdc-us.org. Then check with your local and state governments and your local chamber of commerce.