Hmmm, theres - hunt through their gallery because there's some really good background pieces they have made - completely amazing at characters + backgrounds - They do lots of landscapes which look fabulous!
And obcourse you probably know Griffsnuff too XD she's like the background god.
TamberElla. And now she is doing color practice, whitch is more of a weather one and you can see how to make the same background in different periods of the year There's also DetecriveFE who does amaizing light and light stains, especialy in this drawing crescent-children.deviantart.c…
i myself am getting pretty good at backrounds, but self promotion aside there is Hungrier, volinfer, Daemon-illusionum, pokituu, yechii and TIFFASHY and a couple of others that i probably missed, but definately check those artists out!