Forbes went to the trouble of calculating the cost per win for every member of a major conference team from 2009 through 2011, and what they found is that NC State is among the better bang-for-your-buck options in college football. But that's not really what we're talking about here.
The Wildcats spent an average $1,445,623 per victory over the last three seasons. They are closely followed by the Stanford Cardinal ($1,522,942 per win) and NC State Wolfpack ($1,580,752 per win).
This sort of thing can be instructive in professional sports, but I don't think there is much utility to it on the collegiate level. You know, since the players are unpaid and there's no free agency and et cetera. If NC State switched budgets with the brand name schools in college football, it would still be out-recruited, and the financials would paint an entirely different picture. This is the interesting bit: BCS schools averaged $53 million in expenditures ($17.7 million per year) over the three years of this study. NC State spent $36 million, which was more than just two BCS conference schools (UConn, Ole Miss).
This is not to say that winning at a high level is impossible with this sort of spending--Kansas State is in the same neighborhood, though it benefits from the Bill Snyder voodoo--but it's a good illustration of the challenges NC State's football program faces.
Obviously, how that money is allocated is a crucial part of the story. NC State may be using its available resources more efficiently than other schools, which is what this list implies. It's the recruiting budget that probably would be most telling.
Fundamentally, some sort of "cost per stars" number might be more useful. Because that's ultimately what matters--are you bringing in blue chip talent with the money you're spending? Or just talent on par with your budget? If the wins don't come in proportion with the talent on hand, then that's coaching, not wasteful spending. Process, not outcome. But coaches' salaries go into the expenditures and oh I've gone cross-eyed.