WordNet (r) 3.0 (2006):

popeyed
    adj 1: with eyes or mouth open in surprise [syn: goggle-eyed,
           openmouthed, popeyed]
    2: having bulging eyes

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "popeyed":
   agape, aghast, agog, all agog, amazed, astonished, astounded,
   at gaze, awed, awestruck, beguiled, bellied, bewildered, bewitched,
   breathless, bug-eyed, bulged, captivated, cockeyed, confounded,
   cross-eyed, dumbfounded, dumbstruck, enchanted, enraptured,
   enravished, enthralled, entranced, exophthalmic, fascinated,
   flabbergasted, gaping, gauping, gazing, glare-eyed, goggle,
   goggled, hypnotized, in awe, in awe of, lost in wonder, marveling,
   mesmerized, monocular, moon-eyed, one-eyed, open-eyed, openmouthed,
   overwhelmed, pouched, puzzled, rapt in wonder, saucer-eyed,
   spellbound, staggered, staring, stupefied, surprised, swivel-eyed,
   swollen, thunderstruck, tumescent, tumid, tumorous, turgescent,
   turgid, under a charm, ventricose, walleyed, wide-eyed,
   wonder-struck, wondering