Atlanta also isn't a crewbase. I would think that the Conductors are the crewmembers in need of training, not the Engineers.
The conductor bases in 2006 according to Trains Magazine are as follows:
(On corridors where it isn't clear which base covers what train, I will list the potentials. Richmond through NY I will consider "NEC" for simplicity)
Sunset- Los Angeles, El Paso, San Antonio, New Orleans
SW Chief- Los Angeles, Albuquerque, La Junta, Kansas City, Chicago
Zephyr- Oakland, Sparks, Salt Lake, Denver, Chicago
Builder- (Portland), Seattle, Shelby, St. Cloud, Chicago
Starlight- (Los Angeles or San Luis Obispo), Sacramento, Portland, (Possibly Seattle)
Crescent- Meridian, Charlotte, NEC
Eagle- San Antonio, Fort Worth, Little Rock, Chicago
Capitol- Toledo, Washington
Lake Shore- Toledo, Albany
Cardinal- Indianapolis, Huntington, NEC
City of NOL- New Orleans, Carbondale (Possibly Chicago)
Carolinian- Raleigh, NEC
Palmetto- Florence, NEC
Silver Star- Miami, Jacksonville, Raleigh, NEC
Silver Meteor- Jacksonville, (Possibly Florence), NEC
Regional- Richmond, Washington, Philadelphia, New York, New Haven, Boston
Other possible routes
Pennsylvanian- Harrisburg, NEC
Vermonter- NEC, Springfield
Adirondack, Ethan Allen, and Maple Leaf- Albany