Let me preface by saying that I calculated every player's salary by their annual average salary over the length of their contract because that is how they are calculated for the purpose of the luxury tax threshold. All figures are in millions and rounded to to the 100th.
Players Under Contract
Gonzalez - 20.71
Crawford - 20.29
Beckett - 17
Lackey - 16.5
Youkilis - 10.31
Matsuzaka - 8.67
Buchholz - 7.49
Pedroia - 6.75
Jenks - 6
Lester - 6
Iglesias - 2.06
Scutaro - 1.5 (cost of buyout)
These arbitration estimates are based on the 40/60/80 rule with two exceptions. According to the 40/60/80 rule, Ellsbury would make over $20 million next year and he's obviously not going to. For a comp, I used the $12 million that Josh Hamilton asked for coming off an MVP season and downgraded it to reflect the fact that Ellsbury is in his second year of arbitration, not his third. For Morales, his salary would have been below league minimum, so I simply increased it by 20%.
Arbitration Eligible Players
Ellsbury - 10
Saltalamacchia - 5.6
Albers - 4.28
Bard - 2.97
Lowrie - 1.32
Aceves - 0.99
McDonald - 0.88
Morales - 0.51
That would give us a salary of $149.83 million going into next year. If you round out the rest of the 40-man with players making an average of 0.50 million a year, that would mean our base salary going into 2012 sits at $159.83 million. The luxury tax threshold in 2012 will be $186 million. If you reserve $5 million for contract bonuses, that leaves us with just over $21.17 million to work with in free agency next year to sign a DH, a starter, a closer, a backup catcher and possibly a right fielder. Some of those arbitration figures look a little high though so that's probably a slightly conservative estimate.