convmv is a great tool for changing filenames from 
one encoding to another.  example commands:

# recursive conversion from windows code page (or close to
# it) into utf-8 encoding.  this just tests to see if all
# the intended conversions would work.
convmv -r -f iso8859-1 -t utf-8 *

# convert from wacky utf-7 format into utf-8 format.
# this assumes a prior test was done and actually does
# the name conversions.
convmv --notest -r -f utf-7 -t utf-8 *