Holy crap, what a find! From Dangerous Minds:
Blue Velvet’s original shooting script is reputed to have been over four hours long. The theatrical release came in at 120 minutes. An additional hour of deleted footage was thought to have been lost when the producer of the film, Dino De Laurentis, sold his company. Fortunately, the footage was located and was released as an extra on the Blu-ray edition of Blue Velvet . These deleted scenes have been uploaded to YouTube and I present them here for your viewing pleasure. Rumor has it that there is even more footage out there.
Things kick off with a bang in a barroom scene with Jeffrey Beaumont, Frank Booth, a bevy of prostitutes, an old dude singing some deranged blues tune, violence on a pool table and a woman with glowing nipples.
Knowing Lynch, I would guess this is NSFW: