Author: Michael Hosticka
Completely worth to take the 3-day trial and watch this tutorial series. I highly recommend it.
Author: Multiple Artists
Site: Polycount Wiki
This article contains good details about normal map baking, its workflow and cool tips to solve issues.
Author: Xavier Coelho-Kostolny
Full Character Materials and Rendering Workshop Playlist
Author: Dan John Cox
Price: $29 / Month