Start by getting the Open Railway Map website. The routes are on the map with subdivision names and yard names. Then use the RRDB to find the frequencies of interest. These will get you started: 161.190 - CN McComb Sub; 160.230 - NS Back Belt Line; 161.490 - NS interchange to CPKC @ Metairie; 161.28 - CN yard operations; 160.440 - NO passenger terminal