One advantage of working for Deutsche Bahn is you have information about trains and its operations (only publicly available information are published here). DB Projektbau GmbH, a subsidiary of DB Netze (railway infrastructure company) published a coffee-table book about their infrastructure projects in 2012. I won this book through an internal lucky draw.
This wonderful book (in German/Deutsch) is available for Eurailpress from 48 Euro. A good book to have if you want to follow the construction guidelines of tunnels, bridges and right-of-ways of DB. Definitely an idea book for my N-scale layout.