Hey, these are the best professional tutorials available so far. The engine is still really new so as time passes more will come. Usually these videos will only hone in on one specific task, like lighting, vfx, bluprints etc. But it is the best option other then hunting individual videos on youtube that a lot of channels have no consistency. If anyone knows of some pro tuts that slipped pass me i would like to know the publisher.
Go to these websites and look under the game art section. Tons of tutorials but not many related to the new engine yet. If you want to learn 3d art you are set, tons of those available. Digital Tutors, Lynda, Eat3d, 3Dmotive all have great game art related tutorials.
If you are looking for professional videos that only utilize free programs like gimp and blender i think that will be hard to find, these publishers usually cover the most popular software.
Here is the professional videos i have come acroos so far for ue4,