The Collaborative International Dictionary of English v.0.48:

Methodic \Me*thod"ic\, Methodical \Me*thod"ic*al\, a. [L.
   methodicus, Gr. ?: cf. F. m['e]thodique.]
   1. Arranged with regard to method; disposed in a suitable
      manner, or in a manner to illustrate a subject, or to
      facilitate practical observation; well-ordered; as, the
      methodical arrangement of arguments; a methodical
      treatise. [WordNet sense 2] "Methodical regularity."
      --Addison.
      [1913 Webster]

   2. Proceeding with regard to method; characterized by method
      or orderliness; systematic; as, a methodical
      investigation. [WordNet sense 1] "Aristotle, strict,
      methodic, and orderly." --Harris.
      [1913 Webster]

   3. Of or pertaining to the ancient school of physicians
      called methodists. --Johnson.
      [1913 Webster] -- Me*thod"ic*al*ly, adv. --
      Me*thod"ic*al*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

methodical
    adj 1: characterized by method and orderliness; "a methodical
           scholar"

Moby Thesaurus II by Grady Ward, 1.0:

81 Moby Thesaurus words for "methodical":
   accordant, alike, analytical, arranged, automatic, balanced,
   businesslike, careful, consistent, consonant, constant, continuous,
   correspondent, deliberate, disciplined, equable, equal, even,
   exact, flat, formal, habitual, harmonious, homogeneous, immutable,
   in hand, invariable, labored, laborious, level, logical, measured,
   mechanical, methodic, methodized, meticulous, monolithic, neat,
   normal, of a piece, ordered, orderly, organized, paced,
   painstaking, persistent, plodding, precious, precise, precisian,
   precisionist, punctilious, puristic, regular, regular as clockwork,
   robotlike, routine, scrupulous, smooth, stable, steadfast, steady,
   structured, symmetrical, systematic, systematized, tidy, unbroken,
   unchangeable, unchanged, unchanging, undeviating, undifferentiated,
   undiversified, uniform, unruffled, unvaried, unvarying, usual,
   well-ordered, well-regulated