The word uses the intensifier function of “be-” to strengthen the lost-ness of archaic verb “wilder” – to lose one’s way or be pathless.  It’s in common use, although the root verb is archaic.  Wouldn’t that be a lovely word to encounter in a story?  Wildered?  We do have wilderland and wilderness coming up.  After all, we “are come to the very edge of the Wild,” (03.006).

• 01.048 and altogether bewildered
• 05.148 while bewildered goblins were still picking up
• 17.025 so strong was the bewilderment of the treasure upon him,
• 18.021 and bewildered among their foes.

“bewilder, v.” OED Online. Oxford University Press, March 2015. Web. 6 May 2015.