Question Sources for environment resources

[cyran lycan]

I am interested in simple (floor plus skybox) and complex (backdrop type scenes such as a forest or city or such) environment assets though my various keyword searches in the resources section of this hub haven't produced the amount of these types of things that I assume exist given various videos producers have posted around (having done the video within VaM). Mostly interested in free assets though would pay nominal fees for some things. Anyone have suggestions for sources of such assets?