The Collaborative International Dictionary of English v.0.48:

Available \A*vail"a*ble\, a.
   1. Having sufficient power, force, or efficacy, for the
      object; effectual; valid; as, an available plea. [Obs.]
      [1913 Webster]

            Laws human are available by consent.  --Hooker.
      [1913 Webster]

   2. Such as one may avail one's self of; capable of being used
      for the accomplishment of a purpose; usable; profitable;
      advantageous; convertible into a resource; as, an
      available measure; an available candidate.
      [1913 Webster]

            Struggling to redeem, as he did, the available
            months and days out of so many that were
            unavailable.                          --Carlyle.
      [1913 Webster]

            Having no available funds with which to pay the
            calls on new shares.                  --H. Spenser.
      [1913 Webster]

WordNet (r) 3.0 (2006):

available
    adj 1: obtainable or accessible and ready for use or service;
           "kept a fire extinguisher available"; "much information
           is available through computers"; "available in many
           colors"; "the list of available candidates is unusually
           long" [ant: unavailable]
    2: not busy; not otherwise committed; "he was not available for
       comment"; "he was available and willing to accompany her"
       [syn: available, uncommitted]
    3: convenient for use or disposal; "the house is available after
       July 1"; "2000 square feet of usable office space" [syn:
       available, usable, useable]

Moby Thesaurus II by Grady Ward, 1.0:

78 Moby Thesaurus words for "available":
   abandoned, accessible, adaptable, all-around, approachable,
   at hand, at leisure, at liberty, at loose ends, attainable,
   attendant, close by, come-at-able, convenient, deserted,
   disengaged, fallow, findable, forsaken, free, getatable, gettable,
   godforsaken, handy, idle, immanent, immediate, in view, indwelling,
   inherent, jobless, leisure, leisured, lumpen, nearby, obtainable,
   of all work, off, off duty, off work, on board, on call, on deck,
   on hand, on tap, open, open to, otiose, out of employ,
   out of harness, out of work, penetrable, pervious, present,
   procurable, reachable, ready, securable, tenantless, to be had,
   to hand, unemployable, unemployed, unfilled, uninhabited, unmanned,
   unoccupied, unpeopled, unpopulated, unstaffed, untaken, untenanted,
   untended, vacant, versatile, within call, within reach,
   within sight