Research.

These are a few websites I came across when researching sustainable and vegetable ink printing. 

http://www.ecographic.co.uk/ink.htm

The above website is a graphic design company that also deal in the environmental concerns. It gives you a quick overview of eco - printing and inks.

http://www.blog.upstream.coop/2010/10/what-are-vegetable-based-inks/

Having not known very much about vegetable inks and FSC materials etc. This helped me to understand the basics of the environmental impacts normal inks can have and by using vegetable inks it can reduce the negative effects.

http://www.alocalprinter.com/uk/green-printing/

This website has a 'green printing' policy in place to ensure customers of what they are receiving with the service. This is just one company that strives to do more to help retain the environment in which we live in.