On my Mac OS, Text Wrangler identified a CSV file created with Excel as having "Western" encoding.
After some googling I have made this small script (I am not sure about Windows availability, maybe with Cygwin?):
$ cat /usr/local/bin/utf8.sh
#!/bin/bash
INPUTFILE="$1"
iconv -f macroman -c -t UTF-8 $INPUTFILE |tr '\r' '\n' >/tmp/file.$$.csv
mv $INPUTFILE ms_trash
mv /tmp/file.$$.csv $INPUTFILE