In total the squad is worth £4, 7 shillings & 6p plus all the pies Andy Robinson can eat in a week, plus all the pints of Sam Smiths I can drink in a month. So around 30m. But as someone else said, depends on who's buying. Double that if Leicester are in the market, & treble it if Ridsdale is the negotiator!!!
I'm hazarding a guess, but if I were to carry out due diligence on Leeds Utd FC and in particular their assets, then the contracts each player has must be taken into consideration. For what it is worth, I would suggest that on current value, the entire squad would be valued between £8 - £12m. What clubs actually pay for a player is different, as they take into account future value, wages etc.