WordNet (r) 3.0 (2006):

not surprised
    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:

31 Moby Thesaurus words for "not surprised":
   agape, agog, all agog, anticipant, anticipating, anticipative,
   anticipatory, awaiting, certain, confident, eager, expectant,
   expecting, forearmed, forestalling, forewarned, gaping, hopeful,
   in anticipation, in expectation, looking for, looking forward to,
   optimistic, prepared, ready, sanguine, sure, unsurprised, waiting,
   waiting for, watching for