The best and most up to date vehicle rules for the
40K RPG line are in the Only War Core Rulebook*. They contain a number of common vehicles, plus you should be able to use them to make up your own vehicles fairly easily.
The Black Crusade
GM kit contains an adventure as well as a small section on running campaigns - some general
GM advice really. The main draw is the
GM screen, which is really nice.
*Full Disclosure: I wrote the vehicle rules.