http://www.mp3-box.org/flv-to-mp3-youtube-converter/
Is YouTube to MP3 illegal?
I was wondering if it is illegal to download the MP3 from a FLV video on youtube, using an online converter. I will not be distributing the music (personal use only), and therefor will also not be making money off it.
Please no “If you one catches you, its not illegal 
“. I’m looking for factual answers only. Thanks 
No, you can download youtube and convert it to mp3 with youtube download hd on this site: www.1videoconverter.com i usually do it, so don’t worry!
The Best FLV Converter – Convert YouTube FLV to MP3, MP4, AVI, MOV, 3GP