I doubt very much that this information is in the public domain.
You only have to show abbreviated accounts at Companies House - which essentially is the balance sheet. So, unless the clubs concerned are willing to share the information theres no obligation to declare it.
That said, one of the big firms (think is might have been PWC) did put out a report a year or so back on wages vs turnover.
It was the year that the sheepshaggers got promoted - and they topped the badboys list with wages being far in excess of turnover.
Shame, be interesting to see how Derby's artificially high attendances translated into spending power, or lack thereof.
There's quite a good book out there called Why England Lose that argues that the success of a club is more or less proportional to how high their wage bill is, and that transfer spending has little to do with it. Not sure I fully agree but they present a convincing argument.