From Propublica here is an interactive list which shows each Congressperson and Senator who are FOR SOPA. The list allows you to link to a page related to the politicians as well as send them an email.
Louisiana's Landrieu, Scalise and Vitter are SOPA supporters.
From the website:
Well-funded interests on either side of SOPA and PIPA are lining up support among members of Congress. This database keeps track of where members of Congress stand. Findings are based on two factors: whether a member is a sponsor of the proposed bills, and each member's voting record on the current bills' precursors and alternatives. Click the links on the left to filter the supporters list.