SlashDot and NewsForge seem primarily concerned with the SSSCA's impact on Open Source software, and rightly so. The implications of the SSSCA on Open Source software aren't widely understood, nor are the freedom issues behind Open Source software and their importance. Perhaps part of the Open Source concern, the thing that scares me most about the SSSCA is its primary effect: to broadly regulate all data technology to what moneyed industry groups decide.
Congress.org is one of many places where you can look up your representatives' contact information.