Oh, it's not explicitly stated in canon anywhere; just the general sneering arrogant way they throw money around, the way they never actually brag about the *specifics* of their lineage, Rita calling their house a mansion rather than a manor or estate, the way the old-school purebloods like the Longbottoms and the Blacks (and even the Weasleys) talk about them -- all of that says 'new money' to me without it ever being stated outright. But that's a long-standing debate in the fandom.

I picked Upstate New York for the Weasleys because it needed to be a place where they could *think* that they're aristocrats, while actually *being* just as trashy as the worst of Alabama rednecks, so, yeah, not so far off. That whole getting drunk and wrapping your car around a tree for fun sounds *entirely* plausible. Considering Ron actually *did* it in canon... Yeah.