WordNet (r) 3.0 (2006):

unsurprised
    adj 1: not surprised or expressing surprise; "that unsuprised
           obstinate look on his face" [syn: unsurprised, not
           surprised] [ant: surprised]

Moby Thesaurus II by Grady Ward, 1.0:

50 Moby Thesaurus words for "unsurprised":
   agape, agog, all agog, anticipant, anticipating, anticipative,
   anticipatory, awaiting, aweless, calm, certain, composed,
   confident, cool, eager, expectant, expected, expecting, forearmed,
   forestalling, forewarned, gaping, hopeful, in anticipation,
   in expectation, inexcitable, looking for, looking forward to,
   not surprised, optimistic, prepared, ready, sanguine, sure,
   unamazed, unastonished, unastounded, unawed, unbewildered, undazed,
   undazzled, undumbfounded, unimpressed, unmarveling, unmoved,
   unwondering, waiting, waiting for, watching for, wonderless