I am looking for eco-friendly caterers for a casual wedding. Any suggestions?
No doubt you meant the wedding will be "informal," not "casual" ("done without serious intent or commitment"). Why not use a restaurant or banquet hall centrally located relative to the guests (and near public transportation), so that you don't add the pollution of catering trucks puffing along city streets or require more driving than necessary from attendees?
Check out wastelessliving.com. It's hard to tell from the website but they will help you organize everything but the food for eco-friendliness for parties. We used her for a big school fundraiser. And she is great to talk to and may have some food ideas as well. I think they are located in the Pasadena area.
I would highly recommend Schaffer's Genuine Foods. They take locavore eating to a new level. Everything on their menu is made with sustainable and eco-conscious products. They also compost all food scraps, recycle all plastics and use disposable products that decompose in landfills in just 50 days. They minimize their carbon footprint by highlighting local and seasonal foods in their menu. They are located in Los Angeles (Venice).