eng2audio.sh

#!/bin/bash
# Created:       19-05-2013 19:00h
# Last Change:   21-05-2013 10:39h
# Author:        Sergio Luiz Araujo Silva
# Site:          http://vivaotux.blogspot.com/
# Twitter:       @voyeg3r
# this script gets the mp3 version of one given string from google translate
# references: 
# http://stackoverflow.com/questions/9163988/download-mp3-from-google-translate-text-to-speech
# http://www.commandlinefu.com/commands/view/8044/google-text-to-speech-in-mp3-format
# http://saironiq.blogspot.com.br/2011/03/google-text-to-speech-api.html
# http://crunchbang.org/forums/viewtopic.php?id=17034
# http://lifehacker.com/5426797/google-translate-url-generates-instant-text+to+speech-mp3-files

# próximo passo tornar esse script mais legível

FILENAME="${@:?Usage: $0 give me some words to speech}"
FILENAME=`awk '{print tolower($0)}' <<< "$FILENAME"`
#[ "${#FILENAME}" -gt 100 ] &&  echo "Only strings smaller than 100 chars" && exit 1
# FILENAME="${FILENAME// /+}+' '"
 ! ping -n -c 4 -i 0.2 -W1 www.google.com  > /dev/null   &&  echo 'Connection error!' || \
wget -q -U Mozilla -O "${FILENAME// /_}.mp3" "http://translate.google.com/translate_tts?ie=UTF-8&tl=en&q=${FILENAME// /+}+' '"
[ -f "${FILENAME// /_}.mp3" -a ! -s "${FILENAME// /_}.mp3" ] && { rm -f "${FILENAME// /_}.mp3" ; exit 1 ; }
command -v mpg321 > /dev/null  && mpg321 -q "${FILENAME// /_}.mp3"

Another solution to put "+" between words of the given string is using somthing like
local IFS=+
but we need change this to underline when saving file.mp3