http://www.epic.org The Electronic Privacy Information Center, is a serious group that addresses issues of concern just like this one and is worth checking out.
http://www.eff.org/ is another serious group and here's their description in their own words:
The Electronic Frontier Foundation is the leading civil liberties organization working to protect rights in the digital world. Founded in 1990, EFF actively encourages and challenges industry and government to support free expression, privacy, and openness in the information society. EFF is a member-supported organization and maintains one of the most linked-to Web sites in the world.
These organizations aggregate concerns and address them within the political system, so I recommend to anyone concerned with mail blocking that you write down your thoughts and direct them to this organization.
Please be well.
Kim Brooks Wei ? P O Box 626 ? Fair Lawn ? NJ 07410 ? V 201.475.1854