The KCS yard in New Orleans is easy to find. It is located right along Airline Highway (US61) and can easily be accessed from the I-10 offramp. The first road to the south (coming from downtown NewOrleans) is a subway under the tracks. This is L&A Road. It appears to be private, but in fact is a public street. After you come under the tracks and up to street level you will see the yard office and engine facility right in front of you. There is usually only a couple of yard switchers and one (sometimes two) sets of road power there. Airline Highway is a continuation of Tulane Avenue from the CBD (Central Business District, New Orleanese for downtown) so is really easy to find. Finding something moving in or near the yard is a different matter.
US 61 north of Baton Rouge is not particularly interesting either, with usually two or three different jobs visible working among the many petrochemical complexes there. The only saving grace is that the tracks and the switch jobs are clearly visible from the highway. There is a small yard in Baton Rouge proper and the station, built in 1967, one of the last passenger stations built, is still standing and in use. This is on Foss Street, but again traffic around here can be pretty sparse.
The New Orleans Zephyrs is a Triple-A minor league team which has their new stadium located along Airline Highway in Metarie. The Illinois Central mainline, also used by KCS, runs along the parking lot of this stadium. If you go to the ballgame, purchase a cheap ticket, then sit in the top row on the first base side, you will see both IC (CN) and KCS trains passing by. This is a surefire way of passing a pleasant couple of hours and during a night game, catching at least one KCS train.