The best videos to learn MassTransit are in the Live Coding section. These are the most up-to-date videos detailing how to build applications using MassTransit.
Beyond those videos, there are several other video presentations featuring MassTransit.
Event Driven Architecture (opens new window) Presented at the North Dallas .NET User Group in February, 2010 by Chris Patterson.
Loosely coupled applications with MassTransit and RabbitMq (opens new window) Presented at NDC Oslo 2016 by Roland Guijt (he is also the author of the MassTransit Intro course on Pluralsight)
Messaging with MassTransit (Lightning Talk) (opens new window) Presented at the dotnetsheff User Group in March, 2018 by Kevin Smith.
Others I'm sure, I just need to find them and link them here.