I found a few other webpages that have letters you can print up to send to your representative and senators regarding GMOs. They also have links to send emails, but letters have a greater impact. I'm going to print up and mail a bunch of letters today. Contacting my representatives on issues that are important to me if one of my newer commitments.
This page has letter encouraging mandatory labeling of foods containing GMOs. http://www.thecampaign.org/main_label.php
This page has letters against pharmcrops, meaning crops that have pharmaceuticals in them.
I figure it won't take me but a few minutes to print the letters up and throw them in the mail.