From the pictures I’ve seen most of the professionally printed signs were from Mom’s Demand Action. They also appeared to have a large part in organizing/posting info via their website. I believe Bloomberg gave them lots of cash in the past.
Mom’s Demand Action, sounds like a granny porn site. If they want the big bucks to come rolling in how about something more catchy, like Moms Impugning Legal Firearms, MILF.
AD AGE magazine for the Public Relations and Advertising community ran a widely publicized campaign for professionals to build and post re-printable signs that anyone can download and print in any size from billboard to business card ... or smaller.
Ad Agencies competed and gave awards for the best, which were published in the magazine and a great plus in the portfolio of an aspiring PR community climber. Participation in this type of public service activity is a must for promotion in the PR and advertising community.